Raise Server side button click event from javascript in ajax call

Question

I have a submit button on a page.

Answer 1

Try this

__doPostBack('<%=btDemo.ClientID%>','OnClick');

Note the double underscore at the beginning

This should trigger a postback if the button was clicked by the user

Answer 2

You can get the required JavaScript code from the ClientScriptManager's GetPostBackEventReference method:

Returns a string that can be used in a client event to cause postback to the server.

This is normally used for writing the onclick attributes on controls like the <asp:linkButton>, but you can use it in your jQuery callback as well:

var succeededAjaxFn = function(result) {
  //Raise server side button click event. Dont call click side event anymore.
  <%= Page.ClientScript.GetPostBackEventReference(btnSubmit, String.Empty) %>;
}

The <%= %> block above will write out the following JavaScript for you:

__doPostBack('btnSubmit','')

Which in turn will post back the form to the server in such a way that ASP.NET thinks the button was clicked, and so the server-side btnSubmit_Click is triggered.

Notice that using this method, you can pass in a C# reference to the actual control. You don't need to worry about its client ID, or the correct name and arguments of the __doPostback() JavaScript function. All that is taken care of by the ClientScriptManager when you call this method.