C# passing variables in System.web.services.WebMethod

I am rather rubbish when it comes to AJAX and javascript on general.

I have a WebMethod:

[System.Web.Services.WebMethod] public static string DumpClients() {}

I have this code in a js file:

mainScreen.DumpClients = function() {
    $('#runclientdumpbtn').attr("disabled", "true");
    mainScreen.clientDiv.innerHTML = "";
    $("#loadingimageclientdump").show();
    PageMethods.DumpClients(mainScreen.DumpClientsCallback, mainScreen.DumpClientsFailed);
}
mainScreen.DumpClientsCallback = function(result) {
    if (result) {
        $("#loadingimageclientdump").hide();
        mainScreen.clientDiv.innerHTML = result;
        $('#runclientdumpbtn').removeAttr("disabled");
    }
};
mainScreen.DumpClientsFailed = function(error, u开发者_如何学PythonserContext, methodName) {
    if (error) {
        // TODO: add your error handling
        $("#loadingimageclientdump").hide();
        mainScreen.clientDiv.innerHTML = error.get_message();
        $('#runclientdumpbtn').removeAttr("disabled");
    }
};

Sys.Application.add_load(applicationLoadHandler);
Sys.WebForms.PageRequestManager.getInstance().add_endRequest(endRequestHandler);
Sys.WebForms.PageRequestManager.getInstance().add_beginRequest(beginRequestHandler);

This worked fine, (I admit I do not fully understand this at all), until I needed to access a dropdownlist from the page. As it is a static method I can not directly get it, so I thought I could pass the value back through the webmethod.

The small problem is I have no idea how. I have been Googling it but am not getting anywhere fast. I am working my way through a JQuery book and understanding more of the basics but this is way beyond me at this moment.

I appreciate any and all help and advice, and sorry that I am probably asking a bit of a stupid question.

---

So I decided I was going completely the wrong way and looked for a better way to call the method and found this solution:

  $("#runclientdumpbtn").click(function() {
        var selectedreporttype = $("#<%= dropdownpageID %>").val();

        $.ajax({
            type: "POST",
            url: "default.aspx/ExtractContacts",
            data: "{outputtype:'" + selectedreporttype + "'}",
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: OnContactSuccess,
            failure: OnContactFailure,
            error: OnContactFailure
        });

        startContact();
    });




[WebMethod()]
public static string ExtractContacts(string outputtype)
{
}

Hope this helps someone else.