How to use slice function in js
The JavaScript slice() function extracts the specified range of elements from the array through the arr.slice(start, end) syntax and returns a new array without modifying the original array. It accepts two parameters: start (start index, inclusive) and end (end index, exclusive), where start and end can be negative values, indicating that counting starts from the end of the array. If only one argument is provided, end defaults to the array length. Example: arr.slice(1, 3) extracts elements [2, 3] from array [1, 2, 3, 4, 5].
JavaScript slice() function usage
slice() function extracts the specified range of elements from the array and returns a new array.
Syntax:
arr.slice(start, end)
Parameters:
- start: Start index (including ). If negative, counting starts from the end of the array.
- end: Ending index (exclusive). If negative, counting starts from the end of the array.
Usage:
The slice() function accepts two parameters, indicating the range of elements to be extracted. If only one argument is provided, end defaults to the length of the array.
Example:
Create an array and use slice() to extract elements:
const arr = [1, 2, 3, 4, 5]; // 提取从索引 1 到 3 的元素(不包括索引 3) const slicedArr = arr.slice(1, 3); console.log(slicedArr); // 输出: [2, 3]
Features:
- slice() function does not modify the original array.
- slice() returns a new array containing the specified elements from start to end.
- If start or end is outside the range of the array, the function will use the array length or 0 as the actual index.
- If start and end are equal, the function returns an empty array.
- If start and end are negative values, the function will start counting from the end of the array.
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