Passing .NET objects to method with AJAX

Question

I'm calling a method in my C# code that takes 2 ListBox objects and a GridView as parameters. How do I pass these, what I've tried throws an error saying the parameters are missing.

var visList = document.getElementById("<%= shown_ListBox.ClientID%>");
var hidList = document.getElementById("<%= hidden_ListBox.ClientID%>");
var gv = document.getElementById("<%= hm_GridView.ClientID%>")
$.ajax({
                    type: "POST",
                    url: "heatmap.aspx/manageCol",
                    data: JSON.stringify({visList, hidList, gv}),
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (res) {
                        alert("success");
                    },
                    error: function (res, msg, code) {
                        // log the error to the console
                    } //error
                });

 public static void manageCol(ListBox visList, ListBox hidList, GridView gv)
    {
     //Stuff
    }

Answer 1

1) JSON.stringify({visList, hidList, gv} is sending one object to your webmethod manageCol while it's expecting 3 parameters.

2) you are passing one string object while expecting ListBox, ListBox and GridView items.