How do I change the user agent string of a WebBrowser control?

I am need to have 7 tabs all having web browser controls and each should have different user agent.I saw this and thought how do they do that? http://www.howtogeek.com/howto/18450/change-the-user-agent-string-in-internet-explorer-8/

and using this for as implementation

Changing the user agent of the开发者_如何学JAVA WebBrowser control

works like this if i change one browsers string all get same

User-Agent is an HTTP header field. There are many ways to change it. For Firefox there are definitely plugins you can download that let you modify your HTTP headers on the fly. There is probably a plugin that will let you do do this on a per-tab basis.

This sounds like a browser-specific question. But, in general, when it comes to HTTP, you can send whatever you want. Your browser does it automatically for you, but for Firefox, at least, you can download plugins that give you more control. For other browsers there might be a config file or setting that you can edit.

If you're writing a web browser that lets you do this feature, well, that should be easy as well; the API you are using should let you modify the headers.