JavaScript Array includes() Method

Below is the example of the Array includes() method.

• Example:

  <script>
      var name = [ 'gfg', 'cse', 'geeks', 'portal' ];
  
      a = name.includes('gfg')
  
      // Printing result of includes()
      document.write(a);
  </script>
• Output:

  true

The array.includes() method is used to know either a particular element is present in the array or not and accordingly, it returns true or false i.e, if the element is present, then it returns true otherwise false.

Syntax:

array.includes(searchElement, start)

Parameter: This method accepts two parameters as mentioned above and described below:

• searchElement: This parameter holds the element which will be searched.
• start: This parameter is optional and it holds the starting point of the array, where to begin the search the default value is 0.

Return Value: It returns a Boolean value i.e, either True or False.

Below examples illustrate the Array includes() method in JavaScript:

• Example 1: In this example the method will searched for the element 2 in that array.

  Input : [1, 2, 3, 4, 5].includes(2);
  Output: true

• Example 2: In this example the method will searched for the element 9 in that array.

  Input : [1, 2, 3, 4, 5].includes(9);
  Output: false

Code for the above method is provided below:

Program 1:

<script>

    // Taking input as an array A
    // having some elements.
    var A = [ 1, 2, 3, 4, 5 ];

    // includes() method is called to
    // test whether the searching element
    // is present in given array or not.
    a = A.includes(2)

    // Printing result of includes().
    document.write(a);
</script>

Output:

true

Program 2:

<script>
    // Taking input as an array A
    // having some elements.
    var name = [ 'gfg', 'cse', 'geeks', 'portal' ];

    // includes() method is called to
    // test whether the searching element
    // is present in given array or not.
    a = name.includes('cat')

    // Printing result of includes()
    document.write(a);
</script>

Output:

false

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

• Google Chrome 47.0
• Microsoft Edge 14.0
• Mozilla Firefox 43.0
• Safari 9.0
• Opera 34.0