Why use void(0) in JavaScript?
The void operator evaluates the given expression and then returns undefined. If you have pass 0 as the unary expression operand to the void operator, JavaScript coerces 0 to "false" and returns, but void doesn't care and simply returns undefined, which means "do nothing" . Put them together and you have composed a way to programmatically "do nothing" when a link is clicked. JavaScript Void(0) is often used when, inserting an expression into a web page may produce an unwanted side-effect. You may occasionally encounter an HTML document that uses href="JavaScript:Void(0);" within an < a > element.
<a href="javascript:void(0)" id="doIt">doSomething</a>
A common usage of JavaScript:Void(0) is with hyperlinks. Usually, when the user clicks a link on a page a new page loads, but this is not always the desired course of action. For example, when the user clicks a link on a page, you might want to update the value of a field in a form or the value of a variable. To prevent a page from reloading when a link is clicked, the void(0) function is used.
example
<a href="#" onclick="alert('I am reloading!!!')">Click me!</a>
output

When you click on the above link. Even though the code within it specifies to display a message in an alert box (and this action does take place), the page will reload automatically.
To prevent the page reloading, we can use JavaScript:void(0); within the anchor link.
<a href="javascript:void(0);" onclick="alert('Not reloaded!!!')">Click me!</a>
output

Related Topics
- JavaScript Interview Questions (Part2)
- JavaScript Interview Questions (Part3)
- Is JavaScript a true OOP language?
- Advantages and Disadvantages of JavaScript
- Difference Between JavaScript and ECMAScript?
- What is noscript tag?
- Escaping Special Characters in JavaScript
- What is undefined x 1 in JavaScript?
- JavaScript : Logical Operators
- Difference between '=', '==' and '===' operators?
- How to reload a page using JavaScript?
- How to write html code dynamically using JavaScript?
- How to add html elements dynamically with JavaScript?
- How to load another html page from javascript?
- What Is The Disadvantages Using InnerHTML In JavaScript?
- What is Browser Object Model
- How to detect the OS on the client machine in JavaScript?
- Difference between window, document, and screen in Javascript?
- Difference between the substr() and substring() in JavaScript?
- How to replace all occurrences of a string in JavaScript?
- How to test a string as a literal and as an object ?
- What is Associative Array? How do we use it?
- What is an anonymous function in JavaScript?
- What is the use of 'bind' method in JavaScript?
- Pure functions Vs. Impure functions in javascript
- Is Javascript a Functional Programming Language?
- What's the Difference Between Class and Prototypal Inheritance?
- Javascript, Pass by Value or Pass by Reference?
- How to prevent modification of an object in Javascript?
- What is 'this' keyword in JavaScript?
- How Does Function Hoisting Work in JavaScript?
- What do mean by NULL in Javascript?
- What does the delete operator do in JavaScript?
- What is the Infinity property used for in Javascript?
- Event bubbling and Event Capturing in JavScript?
- What is "strict mode" and how is it used in JavaScript?
- What is the difference between .call() and .apply()?
- Entire content of a JavaScript source file in a function block?
- What is an immediately-invoked function expression?
- What is escape & unescape String functions in JavaScript?
- What is the instanceof operator in JavaScript?
- What Are RESTful (REpresentational State Transfer)Web Services?
- What is Unobtrusive JavaScript & Why it's Important?
- What are JavaScript Cookies?
- Difference between Client side JavaScript and Server side JavaScript
- TypeError: document.getelementbyid(...) is null
- Uncaught TypeError: Cannot read property of undefined In JavaScript
- What's the difference between Null and Undefined?