Question

I have a js function

function(id){
// do a postback here and get the id on the server side  
}

I need to send the id to the server, how could I do this?

any way will do, using additional/hidden controls anything

Answer 1

function(id){
    __doPostBack('', id);
}

On serverside you can access the argument via forms/params collection and the key __EVENTARGUMENT that is an autmatically generated HiddenField:

VB.Net:

Dim ID as String = Request("__EVENTARGUMENT")

or C#:

string ID = Request["__EVENTARGUMENT"];

Understanding the JavaScript __doPostBack Function