Linear Container Vector

NOTE The initial APIs of this module are supported since API version 8. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import Vector from '@ohos.util.Vector';  

System Capability

SystemCapability.Utils.Lang

Vector

Attributes

constructor

constructor()

A constructor used to create a Vector instance.

Example

let vector = new Vector();

add

add(element: T): boolean

Adds an entry at the end of this container.

Parameters

Return value

Example

let vector = new Vector();
let result = vector.add("a");
let result1 = vector.add(1);
let b = [1, 2, 3];
vector.add(b);
let c = {name : "lala", age : "13"};
let result3 = vector.add(c);

insert

insert(element: T, index: number): void

Inserts an entry at the specified position in this container.

Parameters

Example

let vector = new Vector();
vector.insert("A", 0);
vector.insert(0, 1);
vector.insert(true, 2);

has

has(element: T): boolean

Checks whether this container has the specified entry.

Parameters

Return value

Example

let vector = new Vector();
let result = vector.has("Ahfbrgrbgnutfodgorrogorgrogofdfdf");
vector.add("Ahfbrgrbgnutfodgorrogorgrogofdfdf");
let result1 = vector.has("Ahfbrgrbgnutfodgorrogorgrogofdfdf");

getIndexOf

getIndexOf(element: T): number

Obtains the index of the first occurrence of the specified entry in this container.

Parameters

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(2);
vector.add(1);
vector.add(2);
vector.add(4);
let result = vector.getIndexOf(2);

getLastIndexOf

getLastIndexOf(element: T): number

Obtains the index of the last occurrence of the specified entry in this container.

Parameters

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(2);
vector.add(1);
vector.add(2);
vector.add(4);
let result = vector.getLastIndexOf(2);

removeByIndex

removeByIndex(index: number): T

Removes an entry at the specified position from this container.

Parameters

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(2);
vector.add(4);
let result = vector.removeByIndex(2);

remove

remove(element: T): boolean

Removes the first occurrence of the specified entry from this container.

Parameters

Return value

Return value

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.remove(2);

removeByRange

removeByRange(fromIndex: number, toIndex: number): void

Removes from this container all of the entries within a range, including the entry at the start position but not that at the end position.

Parameters

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.removeByRange(2,4);
vector.removeByRange(4,3);
vector.removeByRange(2,6);

replaceAllElements

replaceAllElements(callbackfn: (value: T, index?: number, vector?: Vector<T>) => T, thisArg?: Object): void

Replaces all entries in this container with new entries, and returns the new ones.

Parameters

callbackfn

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.replaceAllElements((value, index) => {
  return value = 2 * value;
});
vector.replaceAllElements((value, index) => {
  return value = value - 2;
});

forEach

forEach(callbackfn: (value: T, index?: number, vector?: Vector<T>) => void, thisArg?: Object): void

Uses a callback to traverse the entries in this container and obtain their position indexes.

Parameters

callbackfn

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.forEach((value, index) => {
  console.log("value:" + value, index)
});

sort

sort(comparator?: (firstValue: T, secondValue: T) => number): void

Sorts entries in this container.

Parameters

comparator

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.sort((a, b) => a - b);
vector.sort((a, b) => b - a);
vector.sort();

subVector

subVector(fromIndex: number, toIndex: number): Vector<T>

Obtains entries within a range in this container, including the entry at the start position but not that at the end position, and returns these entries as a new Vector instance.

Parameters

Return value

Return value

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.subVector(2,4);
let result1 = vector.subVector(4,3);
let result2 = vector.subVector(2,6);

clear

clear(): void

Clears all entries in this container and sets its length to 0.

Return value

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.clear();

clone

clone(): Vector<T>

Clones this container and returns a copy. The modification to the copy does not affect the original instance.

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.clone();

getCapacity

getCapacity(): number

Obtains the capacity of this container.

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.getCapacity();

convertToArray

convertToArray(): Array<T>

Converts this container into an array.

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.convertToArray();

isEmpty

isEmpty(): boolean

Checks whether this container is empty (contains no entries).

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.isEmpty();

increaseCapacityTo

increaseCapacityTo(newCapacity: number): void

Increases the capacity of this container.

Parameters

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.increaseCapacityTo(2);
vector.increaseCapacityTo(8);

trimToCurrentLength

trimToCurrentLength(): void

Trims the capacity of this container into its current length.

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.trimToCurrentLength();

toString

toString(): string

Uses commas (,) to concatenate entries in this container into a string.

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.toSting();

copyToArray

copyToArray(array: Array<T>): void

Copies entries in this container into an array to overwrite elements of the same position indexes.

Parameters

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let array = ["a", "b", "c", "d", "e", "f"];
let result = vector.copyToArray(array);

getFirstElement

getFirstElement(): T

Obtains the first entry in this container.

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.getFirstElement();

getLastElement

getLastElement(): T

Obtains the last entry in this container.

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.getLastElement();

getLastIndexFrom

getLastIndexFrom(element: T, index: number): number

Searches for an entry backward from the specified position index and returns the position index of the entry.

Parameters

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.add("a");
let result = vector.getLastIndexFrom(4,3);

getIndexFrom

getIndexFrom(element: T, index: number): number

Searches for an entry forward from the specified position index and returns the position index of the entry.

Parameters

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.add("a");
let result = vector.getIndexFrom(4, 3);

setLength

setLength(newSize: number): void

Sets a new length for this container.

Parameters

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
vector.setLength(8);
vector.setLength(2);

get

get(index: number): T

Obtains an entry at the specified position in this container.

Parameters

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.get(2);

set

set(index: number, element: T): T

Replaces an entry at the specified position in this container with a given entry.

Parameters

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);
let result = vector.set(2, "A");

[Symbol.iterator]

[Symbol.iterator](): IterableIterator<T>

Obtains an iterator. Each item of the iterator is a JavaScript object.

Return value

Example

let vector = new Vector();
vector.add(2);
vector.add(4);
vector.add(5);
vector.add(4);

// Method 1:
for (let item of vector) { 
  console.log("value:" + item); 
} 

// Method 2:
let iter = vector[Symbol.iterator]();
let temp = iter.next().value;
while(temp != undefined) {
  console.log("value:" + temp);
  temp = iter.next().value;
}