What is 'void' Operator in JavaScript?

JavascriptWeb DevelopmentFront End Technology

The void is an important keyword in JavaScript, which can be used as a unary operator that appears before its single operand, which may be of any type. This operator specifies an expression to be evaluated without returning a value.

Syntax

The syntax of void can be either of the following two −

<head>
   <script>
      <!--
         void func()
         javascript:void func()
         or:
         void(func())
         javascript:void(func())
      //-->
   </script>
</head>

The most common use of this operator is in a client-side javascript: URL, where it allows you to evaluate an expression for its side-effects without the browser displaying the value of the evaluated expression.

Here the expression alert ('Warning!!!') is evaluated but it is not loaded back into the current document.

Example

<html>
   <head>
      <script>
         <!--
         //-->
      </script>
   </head>

   <body>
      <p>Clickthe following, This won't react at all...</p>
      <ahref = "javascript:void(alert('Warning!!!'))">Clickme!</a>
   </body>
</html>
raja
Published on 19-Jan-2018 10:58:01
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