JavaScript Array shift() Method

Below is the example of Array shift() method.

• Example:

  <script>
  function func() {
  
      // Original array
      var array = ["GFG", "Geeks", "for", "Geeks"];
  
      // Checking for condition in array
      var value = array.shift();
  
      document.write(value);
      document.write("<br />");
      document.write(array);
  }
  
  func();
  </script>
• Output:

  GFG
  Geeks, for, Geeks

The arr.shift() method removes the first element of the array thus reducing the size of the original array by 1.

Syntax:

arr.shift()

Parameters: This method does not accept any parameter.

Return value: This function returns the removed first element of the array. If the array is empty then this function returns undefined.

Note: This function can also be used with other javascript objects that behave like the array.

Below examples illustrate the JavaScript Array shift() method:

• Example 1: In this example the shift() method removes the first element of the array, therefore it returns 34.

  var arr = [2, 5, 8, 1, 4];
  document.write(value);
  document.write(arr);
  

  Output:

  34
  234,567,4
  

• Example 2: In this example the shift() method tries to remove the first element of the array, but the array is empty, therefore it returns undefined.

  var arr = [];
  document.write(value);
  document.write(arr)
  

  Output:

  undefined

Code for the above method is provided below:

Program 1:

<script>
function func() {

    // Original array
    var array = [34,234,567,4];

    // Checking for condition in array
    var value = array.shift();

    document.write(value);
    document.write("<br />");
    document.write(array);
}

func();
</script>

Output:

34
234,567,4

Program 2:

<script>
function func() {

    // Original array
    var array = [];

    // Checking for condition in array
    var value = array.shift();

    document.write(value);
    document.write("<br />");
    document.write(array);
}

func();
</script>

Output:

undefined

Supported Browsers: The browsers supported by JavaScript Array shift() method are listed below:

• Google Chrome 1 and above
• Edge 12 and above
• Firefox 1 and above
• Internet Explorer 5.5 and above
• Opera 4 and above
• Safari 1 and above