function GetVar(argname){ 
    query = location.search.substring(1); 
    pairs = query.split("&"); 
    for(i=0; i<pairs.length; i++){ 
       key   = pairs[i].split("=")[0]; 
       value = pairs[i].split("=")[1]; 
       if(key == argname){ 
           return value; 
       } 
    } 
    return ""; 
}