Set Page as Home Page from Javascript

function setHomepage() {

if (document.all) {

   document.body.style.behavior = 'url(#default#homepage)';

   document.body.setHomePage('http://www.google.co.in');

}

else if (window.sidebar) {

   if (window.netscape) {

      try {

          netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");

      }

      catch (e) {

        alert("this action was aviod by your browser,if you want to enable,

please enter about:config in your address line,and change the value of signed.applets.codebase_principal_support to true");

      }

   }

var prefs = Components.classes['@mozilla.org/preferences-service;1']

                      .getService(Components.interfaces.nsIPrefBranch);

prefs.setCharPref('browser.startup.homepage', 'http://www.google.co.in');

  }

}