How to Update Multiple Web Pages Using JavaScript

Using JavaScript, you can create a separate file which contains content for your web page. To update all the pages simultaneously, simply update the JavaScript file.

Pros:

Easy to implement.
Does not rely on any special HTML extension or server configuration.

Cons:

Relies on the user having JavaScript enabled.
Updates are more tricky than other methods.

Step 1: Create JavaScript File

Create a plain text document and name it with a .js extension, for example masterscript.js. Using the JavaScript document.write method, enter the content you want to be displayed on every page like so:

document.write("<div style='color:blue; font-size:12pt;'>");
document.write("© Copyright Myname 2004");
document.write("</div>");

Note: You don't need to include script tags in this file.

Step 2: Add JavaScript Code to Pages

On every page where you want the content to appear, insert the following code:

To change the content on every page, edit the contents of the masterscript.js file.