File Storage

Note：

The APIs of this module are no longer maintained since API version 6. It is recommended that you use @ohos.fileio instead.

The initial APIs of this module are supported since API version 3. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import file from '@system.file';

file.move

move(Object): void

Moves a specified file to a given location.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
srcUri	string	Yes	URI of the file to move.
dstUri	string	Yes	URI of the location to which the file is to move.
success	Function	No	Called when the source file is moved to the specified location successfully. This function returns the URI of the destination location.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.
301	File or directory not exist.

Example

export default {    
  move() {        
    file.move({            
      srcUri: 'internal://app/myfiles1',            
      dstUri: 'internal://app/myfiles2',            
      success: function(uri) {                
        console.log('call success callback success');            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },        
    });    
  }
}

file.copy

copy(Object): void

Copies a file and saves the copy to a specified location.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
srcUri	string	Yes	URI of the file to copy.
dstUri	string	Yes	URI of the location to which the copy is to save. The directory of application resources and URI of the tmp type are not supported.
success	Function	No	Called when the source file is copied and saved to the specified location successfully. This function returns the URI of the destination location.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.
301	File or directory not exist.

Example

export default {    
  copy() {        
    file.copy({            
      srcUri: 'internal://app/file.txt',            
      dstUri: 'internal://app/file_copy.txt',            
      success: function(uri) {                
        console.log('call success callback success');            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },
    });    
  }
}

file.list

list(Object): void

Obtains the list of all files in a specified directory.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of the directory.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

Return values of the success callback

Name	Type	Description
fileList	Array<FileInfo>	File list. The format of each file is as follows: { uri:'file1', lastModifiedTime:1589965924479, length:10240, type: 'file' }

Table1 FileInfo

Name	Type	Description
uri	string	File URI.
lastModifiedTime	number	Timestamp when the file is stored the last time, which is the number of milliseconds elapsed since 1970/01/01 00:00:00 GMT.
length	number	File size, in bytes.
type	string	File type. Available values are as follows: - dir: directory - file: file

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.
301	File or directory not exist.

Example

export default {    
  list() {        
    file.list({            
      uri: 'internal://app/pic',            
      success: function(data) {                
        console.log(data.fileList);            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },        
    });    
  }
}

file.get

get(Object): void

Obtains information about a specified local file.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	File URI.
recursive	boolean	No	Whether to recursively obtain the file list under a subdirectory. The default value is false.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

Return values of the success callback

Name	Type	Description
uri	string	File URI.
length	number	File size, in bytes.
lastModifiedTime	number	Timestamp when the file is stored the last time, which is the number of milliseconds elapsed since 1970/01/01 00:00:00 GMT.
type	string	File type. The values are as follows: - dir: directory - file: file
subFiles	Array	File list.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.
301	File or directory not exist.

Example

export default {    
  get() {        
    file.get({            
      uri: 'internal://app/file',            
      success: function(data) {                
        console.log(data.uri);            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },
    });    
  }
}

file.delete

delete(Object): void

Deletes local files.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of the file to delete, which cannot be an application resource path.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Incorrect parameter.
300	I/O error.
301	File or directory not exist.

Example

export default {    
  delete() {        
    file.delete({            
      uri: 'internal://app/my_file',            
      success: function() {                
        console.log('call delete success.');            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },
    });    
  }
}

file.writeText

writeText(Object): void

Writes text into a specified file.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of a local file. If it does not exist, a file will be created.
text	string	Yes	Character string to write into the local file.
encoding	string	No	Encoding format. The default format is UTF-8.
append	boolean	No	Whether to enable the append mode. The default value is false.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Incorrect parameter.
300	I/O error.

Example

export default {    
  writeText() {        
    file.writeText({            
      uri: 'internal://app/test.txt',            
      text: 'Text that just for test.',            
      success: function() {                
        console.log('call writeText success.');            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },        
    });    
  }
}

file.writeArrayBuffer

writeArrayBuffer(Object): void

Writes buffer data into a specified file.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of a local file. If it does not exist, a file will be created.
buffer	Uint8Array	Yes	Buffer from which the data is derived.
position	number	No	Offset to the position where the writing starts. The default value is 0.
append	boolean	No	Whether to enable the append mode. The default value is false. If the value is true, the position parameter will become invalid.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.

Example

export default {    
  writeArrayBuffer() {       
    file.writeArrayBuffer({           
      uri: 'internal://app/test',           
      buffer: new Uint8Array(8), // The buffer is of the Uint8Array type.
      success: function() {                
        console.log('call writeArrayBuffer success.');            
      },           
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },
    });    
  }
}

file.readText

readText(Object): void

Reads text from a specified file.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of a local file.
encoding	string	No	Encoding format. The default format is UTF-8.
position	number	No	Position where the reading starts. The default value is the start position of the file.
length	number	No	Length of the text to be read (in bytes). The default value is 4096.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

Return values of the success callback

Name	Type	Description
text	string	Text read from the specified file.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.
301	The file or directory does not exist.
302	The size of text to read exceeds 4096 bytes.

Example

export default {    
  readText() {        
    file.readText({            
      uri: 'internal://app/text.txt',            
      success: function(data) {                
        console.log('call readText success: ' + data.text);            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },        
    });    
  }
}

file.readArrayBuffer

readArrayBuffer(Object): void

Reads buffer data from a specified file.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of a local file.
position	number	No	Position where the reading starts. The default value is the start position of the file.
length	number	No	Length of data to read. If this parameter is not set, the reading proceeds until the end of the file.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

Return values of the success callback

Name	Type	Description
buffer	Uint8Array	File content that is read

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.
301	File or directory not exist.

Example

export default {    
  readArrayBuffer() {        
    file.readArrayBuffer({            
      uri: 'internal://app/test',            
      position: 10,            
      length: 200,            
      success: function(data) {                
        console.log('call readArrayBuffer success: ' + data.buffer);            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },
    });    
  }
}

file.access

access(Object): void

Checks whether a specified file or directory exists.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of the directory or file.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.
301	File or directory not exist.

Example

export default {    
  access() {        
    file.access({            
      uri: 'internal://app/test',            
      success: function() {                
        console.log('call access success.');            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },        
    });    
  }
}

file.mkdir

mkdir(Object): void

Creates a specified directory.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of the directory.
recursive	boolean	No	Whether to recursively create upper-level directories of the specified directory. The default value is false.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.

Example

export default {    
  mkdir() {        
    file.mkdir({            
      uri: 'internal://app/test_directory',            
      success: function() {                
        console.log('call mkdir success.');            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },
    });    
  }
}

file.rmdir

rmdir(Object): void

Deletes a specified directory.

System capability: SystemCapability.FileManagement.File.FileIO

Parameters

Name	Type	Mandatory	Description
uri	string	Yes	URI of the directory.
recursive	boolean	No	Whether to recursively delete subfiles and subdirectories of the specified directory. The default value is false.
success	Function	No	Called when the operation is successful.
fail	Function	No	Called when the operation fails.
complete	Function	No	Called when the execution is complete.

One of the following error codes will be returned if the operation fails.

Error Code	Description
202	Invalid parameter.
300	I/O error.
301	File or directory not exist.

Example

export default {    
  rmdir() {        
    file.rmdir({            
      uri: 'internal://app/test_directory',            
      success: function() {                
        console.log('call rmdir success.');            
      },            
      fail: function(data, code) {                
        console.error('call fail callback fail, code: ' + code + ', data: ' + data);            
      },
    });    
  }
}