how to disable back button in asp.net

Please have a look at my answer to a similar question earlier

How to disable back,forward and Refresh functionality in browser?[^]

In short, don't disable the back button - it's not yours to disable. If you're trying to do this because your application 'needs it', then your architecture and general approach is probably incorrect

"..But i have to disable it in every page of my project. How can i do this?"

Why would you ever need to do this? What about if you were on codeproject now and you couldn't use back or any navigation functions, wouldn't you be annoyed?!

If you really want to stop users being able to go back, you could use an approach similar to this link

http://www.codeguru.com/csharp/.net/net_debugging/debugging/article.php/c12891[^]

Have a look at this,

http://aspnetstudymaterials.blogspot.in/2011_11_01_archive.html[^]

You have to paste the code in the master page or all of your pages...
Thank you...

Check out :

1. http://www.htmlgoodies.com/tutorials/buttons/article.php/3478911/Disabling-the-Back-Button.htm[^]
2. http://csharpdotnetfreak.blogspot.com/2009/04/disable-browser-back-button-javascript.html[^]
3. http://www.4guysfromrolla.com/webtech/111500-1.shtml[^]
4. http://www.irt.org/script/311.htm[^]

You can write this functionality on the page where you want back button disabled. If you want all the pages to have back button disabled then the same function can be written in Master Page.

you can check prevoius page via server[page_referrer] in your page, redirect to error page if the previous page is not your desired one.

Just use this code into your Page Load Event:
Response.Cache.SetCacheability(HttpCacheability.NoCache);
Response.Cache.SetExpires(DateTime.UtcNow.AddHours(-1));
Response.Cache.SetNoStore();

Add this script:

<script>history.go(1)</script>

on Head section of page. Hope this will help you