What you can do is create several profiles. Each profile would have their own settings as you want them to be.

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

• FoxyProxy Standard: https://addons.mozilla.org/firefox/addon/foxyproxy-standard/
• AutoProxy: https://addons.mozilla.org/firefox/addon/autoproxy/
• QuickProxy: https://addons.mozilla.org/firefox/addon/quickproxy/

You could use a user.js file and swap that for another version if you need to change the proxy setting. The user.js file is read each time Firefox is started and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.

• http://kb.mozillazine.org/network.proxy.type
• http://kb.mozillazine.org/network.proxy.%28protocol%29
• http://kb.mozillazine.org/network.proxy.%28protocol%29_port

Thanks guys for help ... these topics helped me.

The big thank for cor-el

Edit user.js does what I want ... I tried to edit prefs.js but it didn't work.

Adel Rehan said

Edit user.js does what I want ... I tried to edit prefs.js but it didn't work.

You can't edit the file when Firefox is open. Firefox will write over the file when it closes.

You are right ... I think the only way to change proxy settings is making add-on to change it.

But if you have any other ways to change it told me :D

When are you trying to change the Firefox (proxy) connection setting?

If you want to change these settings while Firefox is running then you can look at the extensions I posted above. With Firefox closed you could use the user.js file or possibly edit the prefs.js file. To make sure that you have the correct syntax it is best to make the changes on the about:config page and make a backup copy of the corresponding lines in the prefs.js file.

If you have various copies of the user.js file each with a complete set of user_pref() lines to set the connection then you can place such a copy in the Firefox profile folder to switch the connection setting and restart Firefox.

Man, I want to change proxy settings programmatically via vb.net or c# like Hide IP Easy not manually.

Regards

Thanks guys the problem is solved.