JavaScript Array.shift() Method Example

The JavaScript Array.shift() method removes the first element from an array and returns that removed element. This method changes the length of the array.

Syntax

arr.shift()
Return value - The removed element from the array; undefined if the array is empty.

JavaScript Array.shift() Method Examples

Example 1: Remove the first element from an array

var array1 = [1, 2, 3];

var firstElement = array1.shift();

console.log(array1);
// expected output: Array [2, 3]

console.log(firstElement);
// expected output: 1

Example 2: Removing an element from an array

The following code displays the myFish array before and after removing its first element. It also displays the removed element:
var myFish = ['angel', 'clown', 'mandarin', 'surgeon'];

console.log('myFish before:', JSON.stringify(myFish));

var shifted = myFish.shift(); 

console.log('myFish after:', myFish); 

console.log('Removed this element:', shifted); 
Output:
myFish before: ["angel","clown","mandarin","surgeon"]
myFish after: (3) ["clown", "mandarin", "surgeon"]
Removed this element: angel

Example 3: Using shift() method in while loop

The shift() method is often used in condition inside while loop. In the following example every iteration will remove the next element from an array until it is empty:
var names = ["Andrew", "Edward", "Paul", "Chris" ,"John"];

while( (i = names.shift()) !== undefined ) {
    console.log(i);
}
// Andrew, Edward, Paul, Chris, John

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