If you are familiar with PHP, where you can use the in_array() function to search value in the Array, and it returns the Boolean value ( TRUE or FALSE ) to Check if values are exists in Array.

There are inbuilt methods in jQuery and JavaScript that return the index position of the value which you can use for the search.

  • how you can check whether an Array already contains a specific value or not.
  • This requires within the program in some cases like –
  • Stop new value from insert if it already exists in an Array.
  • Execute script when the Array contains the particular value.

Methods used to Check if values are exists in Array:

  1. Loop
  2. indexOf()
  3. inArray()

1.Loop

  • First start with a loop.
  • You can easily find the value within an Array by traversing on the Array and check for the value.

Completed Code

<script type='text/javascript'>varnames_arr = ['sonarika','yogesh','sumit','sonarika','vijay','anil'];functioncheckValue(value,arr){var status = 'Not exist';for(vari=0; i<arr.length; i++){var name = arr[i];if(name == value){status = 'Exist';break;    }  }return status;}console.log('status : ' + checkValue('sonarika', names_arr) );console.log('status : ' + checkValue('mayank', names_arr) );</script>
JavaScript

Output:

status : Existstatus : Not exist
Bash

For making your searching process simpler you can use jQuery and JavaScript inbuilt function to Check if values are exists in Array

2.Array.indexOf()

  • It is a JavaScript method that returns the index position of the value. If it doesn’t find the value then it returns -1.
  • It works both with string and an Array.

Syntax :

value-from-which-search.indexOf( search-value );
JavaScript

Completed Code:

<script type='text/javascript'>varnames_arr = ['sonarika','yogesh','sumit','vijay','anil'];var text = "SonarikaBhadoria";// Search in Arrayconsole.log( 'Index : ' + names_arr.indexOf('sumit') );console.log( 'Index : ' + names_arr.indexOf('vishal') );// Search in Stringconsole.log( 'Index : ' + text.indexOf('a') );</script>
JavaScript

Output:

Index : 2Index : -1Index : 3
Bash

3.jQuery.inArray()

  • It is a jQuery function that returns the index position of the value when it finds the value otherwise -1.
  • It also works with string and an Array.

Syntax:

jQuery.inArray( search-value, value-from-which-search);
JavaScript

Example:

<script type='text/javascript'>varnames_arr = ['sonarika','yogesh','sumit','vijay','anil'];var text = "Yogesh singh";// Searching in Arrayconsole.log( 'Index : ' + jQuery.inArray('sumit', names_arr) );console.log( 'Index : ' + jQuery.inArray('vishal', names_arr ));// Searching in String variableconsole.log( 'Index : ' + jQuery.inArray( "e", text ));</script>
JavaScript

Output:

Index : 2Index : -1Index : 3
Bash

4.Conclusion

  • Some of the methods which you can use to search your value in the existing Array. Using this you can remove or replace the duplicate values.
  • If you are using jQuery within your project then you can simply go with inArray() method otherwise you can indexOf() method.