JavaScript Array slice()

slice() Syntax

The syntax of the slice() method is:

arr.slice(start, end)

Here, arr is an array.

slice() Parameters

The slice() method takes in:

• start (optional) - Starting index of the selection. If not provided, the selection starts at start 0.
• end (optional) - Ending index of the selection (exclusive). If not provided, the selection ends at the index of the last element.

slice() Return Value

• Returns a new array containing the extracted elements.

Example 1: JavaScript slice() method

Output

[ 'JavaScript', 'Python', 'C', 'C++', 'Java' ]
[ 'C', 'C++', 'Java' ]
[ 'Python', 'C', 'C++' ]

Example 2: JavaScript slice() With Negative index

In JavaScript, you can also use negative start and end indices. The index of the last element is -1, the index of the second last element is -2, and so on.

Output

[ 'JavaScript', 'Python', 'C', 'C++' ]
[ 'C', 'C++', 'Java' ]

Example 3: JavaScript slice() with Objects as Array Elements

The slice() method shallow copies the elements of the array in the following way:

• It copies object references to the new array. (For example, a nested array) So if the referenced object is modified, the changes are visible in the returned new array.
• It copies the value of strings and numbers to the new array.

Output

{ name: 'David', age: 23 }
{ name: 'Levy', age: 23 }

Recommended Reading: JavaScript Array.splice()