How would I raise an event if my html syntax is the following:

<select runat="server" id="selection" onclick="inputCheck"  />

I tried this in the code behind:

protected void inputCheck(object sender, EventArgs e)
        {
            //doesnt matter because it raised an on click.
        }

Exception:Microsoft JScript runtime error: 'inputCheck' is undefined

Here is an example with jQuery posting back to the server using ajax method, very clean and easy to use. Let me know if you have questions.

--HTML page

<select id="selection" name="selection" />

--Place this following code in the head tag in the html surrounded by the script tags; you must also include the latest jquery code (free download from http://www.jquery.com)

$(document).ready(function()
{
    $("#selection").click(function()
    {
        var selectionValue = $(this).val();
        $.ajax({
            type: "POST",
            url: "CodeBehindPage.aspx/WebMethodName",
            data: "{'input':'" + selectionValue + "'}",
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (msg) {
                //return value goes here if any
            }
        });
    }
});

//Code behind page

[System.Web.Services.WebMethod]
public static bool WebMethodName(string input)
{
    try
    {
        //do something here with the input

        return (true);
    }
    catch(Exception ex)
    {
        throw ex;
    }

}

--This will post the code to the server without any postbacks, which I like. In order to test, set a break point inside of the WebMethodName function and view the input passed in. HTH