@ohos.fileio (File Management)

The fileio module provides APIs for file storage and management, including basic file management, directory management, file information statistics, and stream read and write.

NOTE

• The initial APIs of this module are supported since API version 6. Newly added APIs will be marked with a superscript to indicate their earliest API version.
• The APIs provided by this module are deprecated since API version 9. You are advised to use @ohos.file.fs.

Modules to Import

import fileio from '@ohos.fileio';

Guidelines

Before using the APIs provided by this module to perform operations on a file or directory, obtain the application sandbox path of the file or directory as follows:

 import UIAbility from '@ohos.app.ability.UIAbility';
 import window from '@ohos.window';

 export default class EntryAbility extends UIAbility {
   onWindowStageCreate(windowStage: window.WindowStage) {
     let context = this.context;
     let pathDir = context.filesDir;
   }
 }

For details about how to obtain the application sandbox path, see Obtaining Application File Paths.

fileio.stat

stat(path: string): Promise<Stat>

Obtains file information. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.stat instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "test.txt";
fileio.stat(filePath).then((stat: fileio.Stat) => {
  console.info("getFileInfo succeed, the size of file is " + stat.size);
}).catch((err: BusinessError) => {
  console.info("getFileInfo failed with error:" + err);
});

fileio.stat

stat(path: string, callback: AsyncCallback<Stat>): void

Obtains file information. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.stat instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
fileio.stat(pathDir, (err: BusinessError, stat: fileio.Stat) => {
  // Example code in Stat
});

fileio.statSync

statSync(path: string): Stat

Obtains file information. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.statSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let stat = fileio.statSync(pathDir);
// Example code in Stat

fileio.opendir

opendir(path: string): Promise<Dir>

Opens a directory. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.listFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let dirPath = pathDir + "/testDir";
fileio.opendir(dirPath).then((dir: fileio.Dir) => {
  console.info("opendir succeed");
}).catch((err: BusinessError) => {
  console.info("opendir failed with error:" + err);
});

fileio.opendir

opendir(path: string, callback: AsyncCallback<Dir>): void

Opens a file directory. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.listFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
fileio.opendir(pathDir, (err: BusinessError, dir: fileio.Dir) => {
  // Example code in Dir struct
  // Use read/readSync/close.
});

fileio.opendirSync

opendirSync(path: string): Dir

Opens a directory. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.listFileSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let dir = fileio.opendirSync(pathDir);
// Example code in Dir struct
// Use read/readSync/close.

fileio.access

access(path: string, mode?: number): Promise<void>

Checks whether this process can access a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.access instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.access(filePath).then(() => {
  console.info("Access successful");
}).catch((err: BusinessError) => {
  console.info("access failed with error:" + err);
});

fileio.access

access(path: string, mode?: number, callback: AsyncCallback<void>): void

Checks whether this process can access a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.access instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.access(filePath, (err: BusinessError) => {
  // Do something.
});

fileio.accessSync

accessSync(path: string, mode?: number): void

Checks whether this process can access a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.accessSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
try {
  fileio.accessSync(filePath);
} catch(err: unknown) {
  console.info("accessSync failed with error:" + err);
}

fileio.close⁷⁺

close(fd: number): Promise<void>

Closes a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.close instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.close(fd).then(() => {
  console.info("File closed");
}).catch((err: BusinessError) => {
  console.info("close file failed with error:" + err);
});

fileio.close⁷⁺

close(fd: number, callback: AsyncCallback<void>): void

Closes a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.close instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.close(fd, (err: BusinessError) => {
  // Do something.
});

fileio.closeSync

closeSync(fd: number): void

Closes a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.closeSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.closeSync(fd);

fileio.copyFile

copyFile(src: string|number, dest: string|number, mode?: number): Promise<void>

Copies a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.copyFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let srcPath = pathDir + "srcDir/test.txt";
let dstPath = pathDir + "dstDir/test.txt";
fileio.copyFile(srcPath, dstPath).then(() => {
  console.info("File copied");
}).catch((err: BusinessError) => {
  console.info("copyFile failed with error:" + err);
});

fileio.copyFile

copyFile(src: string|number, dest: string|number, mode: number, callback: AsyncCallback<void>): void

Copies a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.copyFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let srcPath = pathDir + "srcDir/test.txt";
let dstPath = pathDir + "dstDir/test.txt";
fileio.copyFile(srcPath, dstPath, (err: BusinessError) => {
  // Do something.
});

fileio.copyFileSync

copyFileSync(src: string|number, dest: string|number, mode?: number): void

Copies a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.copyFileSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let srcPath = pathDir + "srcDir/test.txt";
let dstPath = pathDir + "dstDir/test.txt";
fileio.copyFileSync(srcPath, dstPath);

fileio.mkdir

mkdir(path: string, mode?: number): Promise<void>

Creates a directory. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.mkdir instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let dirPath = pathDir + '/testDir';
fileio.mkdir(dirPath).then(() => {
  console.info("Directory created");
}).catch((error: BusinessError) => {
  console.info("mkdir failed with error:" + error);
});

fileio.mkdir

mkdir(path: string, mode: number, callback: AsyncCallback<void>): void

Creates a directory. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.mkdir instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let dirPath = pathDir + '/testDir';
fileio.mkdir(dirPath, (err: BusinessError) => {
  console.info("Directory created");
});

fileio.mkdirSync

mkdirSync(path: string, mode?: number): void

Creates a directory. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.mkdirSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let dirPath = pathDir + '/testDir';
fileio.mkdirSync(dirPath);

fileio.open⁷⁺

open(path: string, flags?: number, mode?: number): Promise<number>

Opens a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.open instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.open(filePath, 0o1, 0o0200).then((number: number) => {
  console.info("File opened");
}).catch((err: BusinessError) => {
  console.info("open file failed with error:" + err);
});

fileio.open⁷⁺

open(path: string, flags: number, mode: number, callback: AsyncCallback<number>): void

Opens a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.open instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.open(filePath, 0, (err: BusinessError, fd: number) => {
  // Do something.
});

fileio.openSync

openSync(path: string, flags?: number, mode?: number): number

Opens a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.openSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath, 0o102, 0o640);

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath, 0o102, 0o666);
fileio.writeSync(fd, 'hello world');
let fd1 = fileio.openSync(filePath, 0o2002);
fileio.writeSync(fd1, 'hello world');
class Option {
  offset: number = 0;
  length: number = 4096;
  position: number = 0;
}
let option = new Option();
option.position = 0;
let buf = new ArrayBuffer(4096)
let num = fileio.readSync(fd1, buf, option);
console.info("num == " + num);

fileio.read

read(fd: number, buffer: ArrayBuffer, options?: { offset?: number; length?: number; position?: number; }): Promise<ReadOut>

Reads data from a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.read instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
import buffer from '@ohos.buffer';
import { ReadOut } from '@ohos.fileio';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath, 0o102, 0o640);
let arrayBuffer = new ArrayBuffer(4096);
fileio.read(fd, arrayBuffer).then((readResult: fileio.ReadOut) => {
  console.info("Read file data successfully");
  let buf = buffer.from(arrayBuffer, 0, readResult.bytesRead);
  console.log(`The content of file: ${buf.toString()}`);
  fileio.closeSync(fd);
}).catch((err: BusinessError) => {
  console.info("read file data failed with error:" + err);
});

fileio.read

read(fd: number, buffer: ArrayBuffer, options: { offset?: number; length?: number; position?: number; }, callback: AsyncCallback<ReadOut>): void

Reads data from a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.read instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
import buffer from '@ohos.buffer';
import { ReadOut } from '@ohos.fileio';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath, 0o102, 0o640);
let arrayBuffer = new ArrayBuffer(4096);
fileio.read(fd, arrayBuffer, (err: BusinessError, readResult: fileio.ReadOut) => {
  if (readResult) {
    console.info("Read file data successfully");
    let buf = buffer.from(arrayBuffer, 0, readResult.bytesRead);
    console.info(`The content of file: ${buf.toString()}`);
  }
  fileio.closeSync(fd);
});

fileio.readSync

readSync(fd: number, buffer: ArrayBuffer, options?: { offset?: number; length?: number; position?: number; }): number

Reads data from a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.readSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath, 0o102, 0o640);
let buf = new ArrayBuffer(4096);
let num = fileio.readSync(fd, buf);

fileio.rmdir⁷⁺

rmdir(path: string): Promise<void>

Deletes a directory. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.rmdir instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let dirPath = pathDir + '/testDir';
fileio.rmdir(dirPath).then(() => {
  console.info("Directory deleted");
}).catch((err: BusinessError) => {
  console.info("rmdir failed with error:" + err);
});

fileio.rmdir⁷⁺

rmdir(path: string, callback: AsyncCallback<void>): void

Deletes a directory. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.rmdir instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let dirPath = pathDir + '/testDir';
fileio.rmdir(dirPath, (err: BusinessError) => {
  // Do something.
  console.info("Directory deleted");
});

fileio.rmdirSync⁷⁺

rmdirSync(path: string): void

Deletes a directory. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.rmdirSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let dirPath = pathDir + '/testDir';
fileio.rmdirSync(dirPath);

fileio.unlink

unlink(path: string): Promise<void>

Deletes a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.unlink instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.unlink(filePath).then(() => {
  console.info("File deleted");
}).catch((error: BusinessError) => {
  console.info("remove file failed with error:" + error);
});

fileio.unlink

unlink(path: string, callback: AsyncCallback<void>): void

Deletes a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.unlink instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.unlink(filePath, (err: BusinessError) => {
  console.info("File deleted");
});

fileio.unlinkSync

unlinkSync(path: string): void

Deletes a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.unlinkSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
fileio.unlinkSync(filePath);

fileio.write

write(fd: number, buffer: ArrayBuffer|string, options?: { offset?: number; length?: number; position?: number; encoding?: string; }): Promise<number>

Writes data into a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.write instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath, 0o100 | 0o2, 0o666);
fileio.write(fd, "hello, world").then((number: number) => {
  console.info("write data to file succeed and size is:" + number);
}).catch((err: BusinessError) => {
  console.info("write data to file failed with error:" + err);
});

fileio.write

write(fd: number, buffer: ArrayBuffer|string, options: { offset?: number; length?: number; position?: number; encoding?: string; }, callback: AsyncCallback<number>): void

Writes data to a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.write instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath, 0o100 | 0o2, 0o666);
fileio.write(fd, "hello, world", (err: BusinessError, bytesWritten: number) => {
  if (bytesWritten) {
    console.info("write data to file succeed and size is:" + bytesWritten);
  }
});

fileio.writeSync

writeSync(fd: number, buffer: ArrayBuffer|string, options?: { offset?: number; length?: number; position?: number; encoding?: string; }): number

Writes data to a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.writeSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath, 0o100 | 0o2, 0o666);
let num = fileio.writeSync(fd, "hello, world");

fileio.hash

hash(path: string, algorithm: string): Promise<string>

Calculates the hash value of a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use hash.write instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.hash(filePath, "sha256").then((str: string) => {
  console.info("calculate file hash succeed:" + str);
}).catch((err: BusinessError) => {
  console.info("calculate file hash failed with error:" + err);
});

fileio.hash

hash(path: string, algorithm: string, callback: AsyncCallback<string>): void

Calculates the hash value of a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use hash.write instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.hash(filePath, "sha256", (err: BusinessError, hashStr: string) => {
  if (hashStr) {
    console.info("calculate file hash succeed:" + hashStr);
  }
});

fileio.chmod⁷⁺

chmod(path: string, mode: number): Promise<void>

Changes file permissions. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.chmod(filePath, 0o700).then(() => {
  console.info("File permissions changed");
}).catch((err: BusinessError) => {
  console.info("chmod failed with error:" + err);
});

fileio.chmod⁷⁺

chmod(path: string, mode: number, callback: AsyncCallback<void>): void

Changes file permissions. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.chmod(filePath, 0o700, (err: BusinessError) => {
  // Do something.
});

fileio.chmodSync⁷⁺

chmodSync(path: string, mode: number): void

Changes file permissions. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
fileio.chmodSync(filePath, 0o700);

fileio.fstat⁷⁺

fstat(fd: number): Promise<Stat>

Obtains file information based on an FD. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.stat instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fstat(fd).then((stat: fileio.Stat) => {
  console.info("fstat succeed, the size of file is " + stat.size);
}).catch((err: BusinessError) => {
  console.info("fstat failed with error:" + err);
});

fileio.fstat⁷⁺

fstat(fd: number, callback: AsyncCallback<Stat>): void

Obtains file information based on an FD. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.stat instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fstat(fd, (err: BusinessError) => {
  // Do something.
});

fileio.fstatSync⁷⁺

fstatSync(fd: number): Stat

Obtains file status information based on an FD. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.statSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let stat = fileio.fstatSync(fd);

fileio.ftruncate⁷⁺

ftruncate(fd: number, len?: number): Promise<void>

Truncates a file based on an FD. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.truncate instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.ftruncate(fd, 5).then(() => {
  console.info("File truncated");
}).catch((err: BusinessError) => {
  console.info("truncate file failed with error:" + err);
});

fileio.ftruncate⁷⁺

ftruncate(fd: number, len?: number, callback: AsyncCallback<void>): void

Truncates a file based on an FD. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.truncate instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let len = 5;
fileio.ftruncate(fd, 5, (err: BusinessError) => {
  // Do something.
});

fileio.ftruncateSync⁷⁺

ftruncateSync(fd: number, len?: number): void

Truncates a file based on an FD. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.truncateSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let len = 5;
fileio.ftruncateSync(fd, len);

fileio.truncate⁷⁺

truncate(path: string, len?: number): Promise<void>

Truncates a file based on a file path. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.truncate instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let len = 5;
fileio.truncate(filePath, len).then(() => {
  console.info("File truncated");
}).catch((err: BusinessError) => {
  console.info("truncate file failed with error:" + err);
});

fileio.truncate⁷⁺

truncate(path: string, len?: number, callback: AsyncCallback<void>): void

Truncates a file based on a file path. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.truncate instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let len = 5;
fileio.truncate(filePath, len, (err: BusinessError) => {
  // Do something.
});

fileio.truncateSync⁷⁺

truncateSync(path: string, len?: number): void

Truncates a file based on a file path. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.truncateSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let len = 5;
fileio.truncateSync(filePath, len);

fileio.readText⁷⁺

readText(filePath: string, options?: { position?: number; length?: number; encoding?: string; }): Promise<string>

Reads the text content of a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.readText instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.readText(filePath).then((str: string) => {
  console.info("readText succeed:" + str);
}).catch((err: BusinessError) => {
  console.info("readText failed with error:" + err);
});

fileio.readText⁷⁺

readText(filePath: string, options: { position?: number; length?: number; encoding?: string; }, callback: AsyncCallback<string>): void

Reads the text content of a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.readText instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
class Option {
  length: number = 4096;
  position: number = 0;
  encoding: string = 'utf-8';
}
let option = new Option();
option.position = 1;
option.encoding = 'utf-8';
fileio.readText(filePath, option, (err: BusinessError, str: string) => {
  // Do something.
});

fileio.readTextSync⁷⁺

readTextSync(filePath: string, options?: { position?: number; length?: number; encoding?: string; }): string

Reads the text of a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.readTextSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
class Option {
  length: number = 4096;
  position: number = 0;
  encoding: string = 'utf-8';
}
let option = new Option();
option.position = 1;
option.length = 3;
let str = fileio.readTextSync(filePath, option);

fileio.lstat⁷⁺

lstat(path: string): Promise<Stat>

Obtains information about a symbolic link that is used to refer to a file or directory. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.lstat instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.lstat(filePath).then((stat: fileio.Stat) => {
  console.info("get link status succeed, the size of file is" + stat.size);
}).catch((err: BusinessError) => {
  console.info("get link status failed with error:" + err);
});

fileio.lstat⁷⁺

lstat(path: string, callback: AsyncCallback<Stat>): void

Obtains information about a symbolic link that is used to refer to a file or directory. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.lstat instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.lstat(filePath, (err: BusinessError, stat: fileio.Stat) => {
  // Do something.
});

fileio.lstatSync⁷⁺

lstatSync(path: string): Stat

Obtains information about a symbolic link that is used to refer to a file or directory. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.lstatSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let stat = fileio.lstatSync(filePath);

fileio.rename⁷⁺

rename(oldPath: string, newPath: string): Promise<void>

Renames a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.rename instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let srcFile = pathDir + "/test.txt";
let dstFile = pathDir + '/new.txt';
fileio.rename(srcFile, dstFile).then(() => {
  console.info("File renamed");
}).catch((err: BusinessError) => {
  console.info("rename failed with error:" + err);
});

fileio.rename⁷⁺

rename(oldPath: string, newPath: string, callback: AsyncCallback<void>): void

Renames a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.rename instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let srcFile = pathDir + "/test.txt";
let dstFile = pathDir + '/new.txt';
fileio.rename(srcFile, dstFile, (err: BusinessError) => {
});

fileio.renameSync⁷⁺

renameSync(oldPath: string, newPath: string): void

Renames a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.renameSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let srcFile = pathDir + "/test.txt";
let dstFile = pathDir + '/new.txt';
fileio.renameSync(srcFile, dstFile);

fileio.fsync⁷⁺

fsync(fd: number): Promise<void>

Synchronizes a file. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.fsync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fsync(fd).then(() => {
  console.info("Data flushed");
}).catch((err: BusinessError) => {
  console.info("sync data failed with error:" + err);
});

fileio.fsync⁷⁺

fsync(fd: number, callback: AsyncCallback<void>): void

Synchronizes a file. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.fsync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fsync(fd, (err: BusinessError) => {
  // Do something.
});

fileio.fsyncSync⁷⁺

fsyncSync(fd: number): void

Synchronizes a file. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.fsyncSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fsyncSync(fd);

fileio.fdatasync⁷⁺

fdatasync(fd: number): Promise<void>

Synchronizes the data of a file. This API uses a promise to return the result. fdatasync() is similar to fsync(), but does not flush modified metadata unless that metadata is needed.

NOTE

This API is deprecated since API version 9. Use fs.fdatasync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fdatasync(fd).then(() => {
  console.info("Data flushed");
}).catch((err: BusinessError) => {
  console.info("sync data failed with error:" + err);
});

fileio.fdatasync⁷⁺

fdatasync(fd: number, callback: AsyncCallback<void>): void

Synchronizes the data of a file. This API uses an asynchronous callback to return the result. fdatasync() is similar to fsync(), but does not flush modified metadata unless that metadata is needed.

NOTE

This API is deprecated since API version 9. Use fs.fdatasync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fdatasync (fd, (err: BusinessError) => {
  // Do something.
});

fileio.fdatasyncSync⁷⁺

fdatasyncSync(fd: number): void

Synchronizes the data of a file. This API returns the result synchronously. fdatasync() is similar to fsync(), but does not flush modified metadata unless that metadata is needed.

NOTE

This API is deprecated since API version 9. Use fs.fdatasyncSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let stat = fileio.fdatasyncSync(fd);

fileio.symlink⁷⁺

symlink(target: string, srcPath: string): Promise<void>

Creates a symbolic link based on a file path. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.symlink instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let srcFile = pathDir + "/test.txt";
let dstFile = pathDir + '/test';
fileio.symlink(srcFile, dstFile).then(() => {
  console.info("Symbolic link created");
}).catch((err: BusinessError) => {
  console.info("symlink failed with error:" + err);
});

fileio.symlink⁷⁺

symlink(target: string, srcPath: string, callback: AsyncCallback<void>): void

Creates a symbolic link based on a file path. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.symlink instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let srcFile = pathDir + "/test.txt";
let dstFile = pathDir + '/test';
fileio.symlink(srcFile, dstFile, (err: BusinessError) => {
  // Do something.
});

fileio.symlinkSync⁷⁺

symlinkSync(target: string, srcPath: string): void

Creates a symbolic link based on a file path. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.symlinkSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let srcFile = pathDir + "/test.txt";
let dstFile = pathDir + '/test';
fileio.symlinkSync(srcFile, dstFile);

fileio.chown⁷⁺

chown(path: string, uid: number, gid: number): Promise<void>

Changes the file owner based on a file path. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let stat = fileio.statSync(filePath);
fileio.chown(filePath, stat.uid, stat.gid).then(() => {
  console.info("File owner changed");
}).catch((err: BusinessError) => {
  console.info("chown failed with error:" + err);
});

fileio.chown⁷⁺

chown(path: string, uid: number, gid: number, callback: AsyncCallback<void>): void

Changes the file owner based on a file path. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let stat = fileio.statSync(filePath)
fileio.chown(filePath, stat.uid, stat.gid, (err: BusinessError) => {
  // Do something.
});

fileio.chownSync⁷⁺

chownSync(path: string, uid: number, gid: number): void

Changes the file owner based on its path. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let stat = fileio.statSync(filePath)
fileio.chownSync(filePath, stat.uid, stat.gid);

fileio.mkdtemp⁷⁺

mkdtemp(prefix: string): Promise<string>

Creates a temporary directory. The folder name is created by replacing a string (specified by prefix) with six randomly generated characters. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.mkdtemp instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
fileio.mkdtemp(pathDir + "/XXXXXX").then((pathDir: string) => {
  console.info("mkdtemp succeed:" + pathDir);
}).catch((err: BusinessError) => {
  console.info("mkdtemp failed with error:" + err);
});

fileio.mkdtemp⁷⁺

mkdtemp(prefix: string, callback: AsyncCallback<string>): void

Creates a temporary directory. The folder name is created by replacing a string (specified by prefix) with six randomly generated characters. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.mkdtemp instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
fileio.mkdtemp(pathDir + "/XXXXXX", (err: BusinessError, res: string) => {
  // Do something.
});

fileio.mkdtempSync⁷⁺

mkdtempSync(prefix: string): string

Creates a temporary directory. The folder name is created by replacing a string (specified by prefix) with six randomly generated characters. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.mkdtempSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let res = fileio.mkdtempSync(pathDir + "/XXXXXX");

fileio.fchmod⁷⁺

fchmod(fd: number, mode: number): Promise<void>

Changes file permissions based on an FD. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let mode: number = 0o700;
fileio.fchmod(fd, mode).then(() => {
  console.info("File permissions changed");
}).catch((err: BusinessError) => {
  console.info("chmod failed with error:" + err);
});

fileio.fchmod⁷⁺

fchmod(fd: number, mode: number, callback: AsyncCallback<void>): void

Changes file permissions based on an FD. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let mode: number = 0o700;
fileio.fchmod(fd, mode, (err: BusinessError) => {
  // Do something.
});

fileio.fchmodSync⁷⁺

fchmodSync(fd: number, mode: number): void

Changes the file permissions based on an FD. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let mode: number = 0o700;
fileio.fchmodSync(fd, mode);

fileio.createStream⁷⁺

createStream(path: string, mode: string): Promise<Stream>

Creates a stream based on a file path. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.createStream instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.createStream(filePath, "r+").then((stream: fileio.Stream) => {
  console.info("Stream created");
}).catch((err: BusinessError) => {
  console.info("createStream failed with error:" + err);
});

fileio.createStream⁷⁺

createStream(path: string, mode: string, callback: AsyncCallback<Stream>): void

Creates a stream based on a file path. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.createStream instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
fileio.createStream(filePath, "r+", (err: BusinessError, stream: fileio.Stream) => {
  // Do something.
});

fileio.createStreamSync⁷⁺

createStreamSync(path: string, mode: string): Stream

Creates a stream based on a file path. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.createStreamSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");

fileio.fdopenStream⁷⁺

fdopenStream(fd: number, mode: string): Promise<Stream>

Opens a stream based on an FD. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.fdopenStream instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fdopenStream(fd, "r+").then((stream: fileio.Stream) => {
  console.info("Stream opened");
}).catch((err: BusinessError) => {
  console.info("openStream failed with error:" + err);
});

fileio.fdopenStream⁷⁺

fdopenStream(fd: number, mode: string, callback: AsyncCallback<Stream>): void

Opens a stream based on an FD. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.fdopenStream instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
fileio.fdopenStream(fd, "r+", (err: BusinessError, stream: fileio.Stream) => {
  // Do something.
});

fileio.fdopenStreamSync⁷⁺

fdopenStreamSync(fd: number, mode: string): Stream

Opens a stream based on an FD. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.fdopenStreamSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let ss = fileio.fdopenStreamSync(fd, "r+");

fileio.fchown⁷⁺

fchown(fd: number, uid: number, gid: number): Promise<void>

Changes the file owner based on an FD. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let stat = fileio.statSync(filePath);
fileio.fchown(fd, stat.uid, stat.gid).then(() => {
  console.info("File owner changed");
}).catch((err: BusinessError) => {
  console.info("chown failed with error:" + err);
});

fileio.fchown⁷⁺

fchown(fd: number, uid: number, gid: number, callback: AsyncCallback<void>): void

Changes the file owner based on an FD. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let stat = fileio.statSync(filePath);
fileio.fchown(fd, stat.uid, stat.gid, (err: BusinessError) => {
  // Do something.
});

fileio.fchownSync⁷⁺

fchownSync(fd: number, uid: number, gid: number): void

Changes the file owner based on an FD. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let fd = fileio.openSync(filePath);
let stat = fileio.statSync(filePath);
fileio.fchownSync(fd, stat.uid, stat.gid);

fileio.lchown⁷⁺

lchown(path: string, uid: number, gid: number): Promise<void>

Changes the file owner (owner of the symbolic link, not the file referred to by the symbolic link) based on a file path. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let stat = fileio.statSync(filePath);
fileio.lchown(filePath, stat.uid, stat.gid).then(() => {
  console.info("File owner changed");
}).catch((err: BusinessError) => {
  console.info("chown failed with error:" + err);
});

fileio.lchown⁷⁺

lchown(path: string, uid: number, gid: number, callback: AsyncCallback<void>): void

Changes the file owner (owner of the symbolic link, not the file referred to by the symbolic link) based on a file path. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let stat = fileio.statSync(filePath);
fileio.lchown(filePath, stat.uid, stat.gid, (err: BusinessError) => {
  // Do something.
});

fileio.lchownSync⁷⁺

lchownSync(path: string, uid: number, gid: number): void

Changes the file owner based on a file path and changes the owner of the symbolic link (not the referenced file). This API returns the result synchronously.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let stat = fileio.statSync(filePath);
fileio.lchownSync(filePath, stat.uid, stat.gid);

fileio.createWatcher⁷⁺

createWatcher(filename: string, events: number, callback: AsyncCallback<number>): Watcher

Listens for file or directory changes. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
fileio.createWatcher(filePath, 1, (err, event) => {
  console.info("event: " + event + "errmsg: " + JSON.stringify(err));
});

Readout

Obtains the file read result. This class applies only to the read() method.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Stat

Provides detailed file information. Before calling a method of the Stat class, use the stat() method synchronously or asynchronously to create a Stat instance.

NOTE

This API is deprecated since API version 9. Use fs.Stat instead.

System capability: SystemCapability.FileManagement.File.FileIO

Attributes

isBlockDevice

isBlockDevice(): boolean

Checks whether this file is a block special file. A block special file supports access by block only, and it is cached when accessed.

NOTE

This API is deprecated since API version 9. Use fs.Stat.isBlockDevice instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let filePath = pathDir + "/test.txt";
let isBLockDevice = fileio.statSync(filePath).isBlockDevice();

isCharacterDevice

isCharacterDevice(): boolean

Checks whether this file is a character special file. A character special file supports random access, and it is not cached when accessed.

NOTE

This API is deprecated since API version 9. Use fs.Stat.isCharacterDevice instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let filePath = pathDir + "/test.txt";
let isCharacterDevice = fileio.statSync(filePath).isCharacterDevice();

isDirectory

isDirectory(): boolean

Checks whether this file is a directory.

NOTE

This API is deprecated since API version 9. Use fs.Stat.isDirectory instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dirPath = pathDir + "/test";
let isDirectory = fileio.statSync(dirPath).isDirectory(); 

isFIFO

isFIFO(): boolean

Checks whether this file is a named pipe (or FIFO). Named pipes are used for inter-process communication.

NOTE

This API is deprecated since API version 9. Use fs.Stat.isFIFO instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let filePath = pathDir + "/test.txt";
let isFIFO = fileio.statSync(filePath).isFIFO(); 

isFile

isFile(): boolean

Checks whether this file is a regular file.

NOTE

This API is deprecated since API version 9. Use fs.Stat.isFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let filePath = pathDir + "/test.txt";
let isFile = fileio.statSync(filePath).isFile();

isSocket

isSocket(): boolean

Checks whether this file is a socket.

NOTE

This API is deprecated since API version 9. Use fs.Stat.isSocket instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let filePath = pathDir + "/test.txt";
let isSocket = fileio.statSync(filePath).isSocket(); 

isSymbolicLink

isSymbolicLink(): boolean

Checks whether this file is a symbolic link.

NOTE

This API is deprecated since API version 9. Use fs.Stat.isSymbolicLink instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let filePath = pathDir + "/test";
let isSymbolicLink = fileio.statSync(filePath).isSymbolicLink(); 

Watcher⁷⁺

Listens for the changes of a file. You can call the Watcher.stop() method synchronously or asynchronously to stop the listening.

stop⁷⁺

stop(): Promise<void>

Stops the watcher instance. This API uses a promise to return the result.

System capability: SystemCapability.FileManagement.File.FileIO

Example

let filePath = pathDir + "/test.txt";
let watcher = fileio.createWatcher(filePath, 1, (err, event) => {
  console.info("event: " + event + "errmsg: " + JSON.stringify(err));
});
watcher.stop().then(() => {
  console.info("Watcher stopped");
});

stop⁷⁺

stop(callback: AsyncCallback<void>): void

Stops the watcher instance. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

let filePath = pathDir + "/test.txt";
let watcher = fileio.createWatcher(filePath, 1, (err, event) => {
  console.info("event: " + event + "errmsg: " + JSON.stringify(err));
});
watcher.stop(() => {
  console.info("Watcher stopped");
})

Stream

Provides a stream for file operations. Before calling any API of the Stream class, use createStream() to create a Stream instance synchronously or asynchronously.

NOTE

This API is deprecated since API version 9. Use fs.Stream instead.

close⁷⁺

close(): Promise<void>

Closes the stream. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.Stream.close instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
ss.close().then(() => {
  console.info("File stream closed");
}).catch((err: BusinessError) => {
  console.info("close fileStream  failed with error:" + err);
});

close⁷⁺

close(callback: AsyncCallback<void>): void

Closes this stream. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.Stream.close instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
ss.close((err: BusinessError) => {
  // Do something.
});

closeSync

closeSync(): void

Closes this stream. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.Stream.closeSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Example

let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
ss.closeSync();

flush⁷⁺

flush(): Promise<void>

Flushes this stream. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.Stream.flush instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
ss.flush().then(() => {
  console.info("Stream flushed");
}).catch((err: BusinessError) => {
  console.info("flush failed with error:" + err);
});

flush⁷⁺

flush(callback: AsyncCallback<void>): void

Flushes this stream. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.Stream.flush instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
ss.flush((err: BusinessError) => {
  // Do something.
});

flushSync⁷⁺

flushSync(): void

Flushes this stream. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.Stream.flushSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Example

let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
ss.flushSync();

write⁷⁺

write(buffer: ArrayBuffer|string, options?: { offset?: number; length?: number; position?: number; encoding?: string; }): Promise<number>

Writes data into the stream. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.Stream.write instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
class Option {
  offset: number = 0;
  length: number = 4096;
  position: number = 0;
  encoding: string = 'utf-8';
}
let option = new Option();
option.offset = 1;
option.length = 5;
option.position = 5;
ss.write("hello, world", option).then((number: number) => {
  console.info("write succeed and size is:" + number);
}).catch((err: BusinessError) => {
  console.info("write failed with error:" + err);
});

write⁷⁺

write(buffer: ArrayBuffer|string, options: { offset?: number; length?: number; position?: number; encoding?: string; }, callback: AsyncCallback<number>): void

Writes data to this stream. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.Stream.write instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
class Option {
  offset: number = 0;
  length: number = 4096;
  position: number = 0;
  encoding: string = 'utf-8';
}
let option = new Option();
option.offset = 1;
option.length = 5;
option.position = 5;
ss.write("hello, world", option, (err: BusinessError, bytesWritten: number) => {
  if (bytesWritten) {
    // Do something.
    console.info("write succeed and size is:" + bytesWritten);
  }
});

writeSync⁷⁺

writeSync(buffer: ArrayBuffer|string, options?: { offset?: number; length?: number; position?: number; encoding?: string; }): number

Writes data to this stream. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.Stream.writeSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath,"r+");
class Option {
  offset: number = 0;
  length: number = 4096;
  position: number = 0;
  encoding: string = 'utf-8';
}
let option = new Option();
option.offset = 1;
option.length = 5;
option.position = 5;
let num = ss.writeSync("hello, world", option);

read⁷⁺

read(buffer: ArrayBuffer, options?: { position?: number; offset?: number; length?: number; }): Promise<ReadOut>

Reads data from the stream. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.Stream.read instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

import { BusinessError } from '@ohos.base';
import buffer from '@ohos.buffer';
import { ReadOut } from '@ohos.fileio';
let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
let arrayBuffer = new ArrayBuffer(4096);
class Option {
  offset: number = 0;
  length: number = 4096;
  position: number = 0;
}
let option = new Option();
option.offset = 1;
option.length = 5;
option.position = 5;
ss.read(arrayBuffer, option).then((readResult: ReadOut) => {
  console.info("Read data successfully");
  let buf = buffer.from(arrayBuffer, 0, readResult.bytesRead);
  console.info(`The content of file: ${buf.toString()}`);
}).catch((err: BusinessError) => {
  console.info("read data failed with error:" + err);
});

read⁷⁺

read(buffer: ArrayBuffer, options: { position?: number; offset?: number; length?: number; }, callback: AsyncCallback<ReadOut>): void

Reads data from this stream. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.Stream.read instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
import buffer from '@ohos.buffer';
import { ReadOut } from '@ohos.fileio';
let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
let arrayBuffer = new ArrayBuffer(4096);
class Option {
  offset: number = 0;
  length: number = 4096;
  position: number = 0;
}
let option = new Option();
option.offset = 1;
option.length = 5;
option.position = 5;
ss.read(arrayBuffer, option, (err: BusinessError, readResult: ReadOut) => {
  if (readResult.bytesRead) {
    console.info("Read data successfully");
    let buf = buffer.from(arrayBuffer, 0, readResult.bytesRead);
    console.info(`The content of file: ${buf.toString()}`);
  }
});

readSync⁷⁺

readSync(buffer: ArrayBuffer, options?: { position?: number; offset?: number; length?: number; }): number

Reads data from this stream. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.Stream.readSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Return value

Example

let filePath = pathDir + "/test.txt";
let ss = fileio.createStreamSync(filePath, "r+");
class Option {
  offset: number = 0;
  length: number = 4096;
  position: number = 0;
}
let option = new Option();
option.offset = 1;
option.length = 5;
option.position = 5;
let buf = new ArrayBuffer(4096)
let num = ss.readSync(buf, option);

Dir

Manages directories. Before calling a method of the Dir class, use the opendir() method synchronously or asynchronously to create a Dir instance.

NOTE

This API is deprecated since API version 9. Use fs.listFile instead.

read

read(): Promise<Dirent>

Reads the next directory entry. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 9. Use fs.listFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

import { BusinessError } from '@ohos.base';
dir.read().then((dirent: fileio.Dirent) => {
  console.log("read succeed, the name of dirent is " + dirent.name);
}).catch((err: BusinessError) => {
  console.info("read failed with error:" + err);
});

read

read(callback: AsyncCallback<Dirent>): void

Reads the next directory entry. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 9. Use fs.listFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Example

import { BusinessError } from '@ohos.base';
dir.read((err: BusinessError, dirent: fileio.Dirent) => {
  if (dirent) {
    // Do something.
    console.log("read succeed, the name of file is " + dirent.name);
  }
});

readSync

readSync(): Dirent

Reads the next directory entry. This API returns the result synchronously.

NOTE

This API is deprecated since API version 9. Use fs.listFileSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dirent = dir.readSync();

close⁷⁺

close(): Promise<void>

Closes a directory. This API uses a promise to return the result. After a directory is closed, the FD in Dir will be released and no directory entry can be read from Dir.

NOTE

This API is deprecated since API version 9. Use fs.listFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Example

import { BusinessError } from '@ohos.base';
dir.close().then(() => {
  console.info("close dir successfully");
});

close⁷⁺

close(callback: AsyncCallback<void>): void

Closes a directory. This API uses an asynchronous callback to return the result. After a directory is closed, the FD in Dir will be released and no directory entry can be read from Dir.

NOTE

This API is deprecated since API version 9. Use fs.listFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Example

import { BusinessError } from '@ohos.base';
dir.close((err: BusinessError) => {
  console.info("close dir successfully");
});

closeSync

closeSync(): void

Closes a directory. After a directory is closed, the FD in Dir will be released and no directory entry can be read from Dir.

NOTE

This API is deprecated since API version 9. Use fs.listFileSync instead.

System capability: SystemCapability.FileManagement.File.FileIO

Example

dir.closeSync();

Dirent

Provides information about files and directories. Before calling a method of the Dirent class, use the dir.read() method synchronously or asynchronously to create a Dirent instance.

NOTE

This API is deprecated since API version 9. Use fs.listFile instead.

System capability: SystemCapability.FileManagement.File.FileIO

Attributes

isBlockDevice

isBlockDevice(): boolean

Checks whether this directory entry is a block special file. A block special file supports access by block only, and it is cached when accessed.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dir = fileio.opendirSync(pathDir);
let isBLockDevice = dir.readSync().isBlockDevice();

isCharacterDevice

isCharacterDevice(): boolean

Checks whether a directory entry is a character special file. A character special file supports random access, and it is not cached when accessed.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dir = fileio.opendirSync(pathDir);
let isCharacterDevice = dir.readSync().isCharacterDevice(); 

isDirectory

isDirectory(): boolean

Checks whether a directory entry is a directory.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dir = fileio.opendirSync(pathDir);
let isDirectory = dir.readSync().isDirectory(); 

isFIFO

isFIFO(): boolean

Checks whether this directory entry is a named pipe (or FIFO). Named pipes are used for inter-process communication.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dir = fileio.opendirSync(pathDir);
let isFIFO = dir.readSync().isFIFO(); 

isFile

isFile(): boolean

Checks whether a directory entry is a regular file.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dir = fileio.opendirSync(pathDir);
let isFile = dir.readSync().isFile(); 

isSocket

isSocket(): boolean

Checks whether a directory entry is a socket.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dir = fileio.opendirSync(pathDir);
let isSocket = dir.readSync().isSocket(); 

isSymbolicLink

isSymbolicLink(): boolean

Checks whether a directory entry is a symbolic link.

NOTE

This API is deprecated since API version 9.

System capability: SystemCapability.FileManagement.File.FileIO

Return value

Example

let dir = fileio.opendirSync(pathDir);
let isSymbolicLink = dir.readSync().isSymbolicLink();