The Array slice() method in JavaScript returns selected elements from an array, creating a new array. It selects elements from a specified start index up to, but not including, a specified end index. The original array remains unchanged.
Array slice() Syntax
arr.slice(begin, end);Array slice() Parameters
- begin: This parameter defines the starting index from where the portion is to be extracted. If this argument is missing then the method takes begin as 0 as it is the default start value.
- end: Parameter specifying the end index for extracting a portion from an array, defaulting to array length if undefined, adjusting for exceeding length.
Array slice() Return value
This method returns a new array containing some portion of the original array.
Array slice() Method Examples
Example 1: Extracting elements between two indexes
Here, the slice() method extracts the array from the given array starting from index 2 and including all the elements less than index 4.
function func() {
// Original Array
let arr = [23, 56, 87, 32, 75, 13];
// Extracted array
let new_arr = arr.slice(2, 4);
console.log(arr);
console.log(new_arr);
}func(); |
[ 23, 56, 87, 32, 75, 13 ] [ 87, 32 ]
Explanation
- In the above example we Defines an array arr with values [23, 56, 87, 32, 75, 13].
- Uses the slice method to extract a portion from arr, starting from index 2 (inclusive) to index 4 (exclusive), storing it in new_arr.
- Logs both the original array arr and the extracted array new_arr to the console.
Example 2: Passing no arguments
Here, the slice() method extracts the entire array from the given string and returns it as the answer, Since no arguments were passed to it.
function func() {
//Original Array
let arr = [23, 56, 87, 32, 75, 13];
//Extracted array
let new_arr = arr.slice();
console.log(arr);
console.log(new_arr);
}func(); |
[ 23, 56, 87, 32, 75, 13 ] [ 23, 56, 87, 32, 75, 13 ]
Explanation
- In the above example we Initializes an original array arr with values [23, 56, 87, 32, 75, 13].
- Creates a shallow copy of arr using the slice method without arguments, essentially duplicating the original array.
- Logs both the original array arr and the copied array to the console.
Example 3: Extracting array from index 2
In this example, the slice() method extracts the array starting from index 2 till the end of the array and returns it as the answer.
function func() {
//Original Array
let arr = [23, 56, 87, 32, 75, 13];
//Extracted array
let new_arr = arr.slice(2);
console.log(arr);
console.log(new_arr);
}func(); |
[ 23, 56, 87, 32, 75, 13 ] [ 87, 32, 75, 13 ]
Explanation
- In the above example we Initializes an original array arr with values [23, 56, 87, 32, 75, 13].
- Creates a new array new_arr by extracting elements from index 2 to the end of the original array using the slice method.
- Logs both the original array arr and the extracted array new_arr to the console.
- The extracted array new_arr will contain elements [87, 32, 75, 13].
Example 4: Slicing the nested Array
In this example, the slice() method extracts the elements from the nested array and returns it as the answer.
function func() {
// Original Array
let arr = [23, [87, 32, 75, 27,3,10,18 ,13]];
// Extracted array
let new_arr = arr[1].slice(2, 4);
console.log(arr);
console.log(new_arr);
}func(); |
Output
[23, [87, 32, 75, 27,3, 10, 18, 13 ]]
[ 75, 27 ]
Explanation
- In the above example we Initializes an original array arr with values [23, [87, 32, 75, 27,3, 10, 18, 13 ]]
- Creates a new array new_arr by extracting elements from index 2 till the 4th element from the nested array using the slice method.
- Logs both the original array arr and the extracted array new_arr to the console.
- The extracted array new_arr will contain elements [ 75, 27 ].
We have a complete list of Javascript Array methods, to check those please go through this Javascript Array Complete reference article.