Get QueryString by javascript

function QueryString(name) {
       var AllVars = window.location.search.substring(1);
       var Vars = AllVars.split("&");
       for (i = 0; i < Vars.length; i++) {
           var Var = Vars[i].split("=");
           if (Var[0] == name) return Var[1];
       }
       return "";
   }