by Dinesh Thakur Category: Javascript String

JavaScript replace() Method: To replace information in a string, you can use regular expressions and the JavaScript replace() Method of the String object. The syntax for using the JavaScript replace() Method is as follows:

varname= stringname.replace(regex,newstring);

Consider a variable named myVariable containing the string “Today is Sunday”. You could search and replace “Sunday” with “Monday” with the following example with JavaScript replace() Method:


When you use the JavaScript replace() Method it returns a new string containing the results of performing the replacement. The original string is not altered. For instance, consider assigning the results of the replacement above to a new variable:

var newVar = myVariable.replace("Sunday','Monday");

In this case, myVariable will continue to contain “Today is Sunday” but newVar will contain “Today is Monday”. The following task creates a variable and assigns text to it, replaces that text with new text, and then displays the results in a browser:

1. Open a new HTML document in your preferred HTML or text editor.

2. Create the body of the document with opening and closing body tags:



3. Insert a script block in the body of the document:

<script language="JavaScript">



4. Create a variable named FirstVariable and assign the value “Hello there” to it:

var FirstVariable = "Hello there";

5. Create a second variable named SecondVariable and assign the results of replacing “there” with “Ecomputernotes” to it:

var SecondVariable = FirstVariable.replace("there","ecomputernotes");

6. Display the results of the JavaScript replace() Method the final page looks like

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

" ">

<html xmlns="" xml:lang="en" lang="en">
   <meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />       <title>JavaScript replace() Method </title>
<h1 style="color: blue"> JavaScript replace() Method</h1> <hr />
   <script type="text/javascript">
   var FirstVariable = "Hello there";
   var SecondVariable = FirstVariable.replace("there","Ecomputernotes");    document.write(SecondVariable);

Save the file and close it.

8. Open the file in a browser. You should see the text “Hello Ecomputernotes” displayed in the browser as in Figure

JavaScript replace() Method

About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.