How to get data from Ajax

Question

I have a variable called sid which handle number of seat. I want to throw sid to TryJSON.aspx method test . then I wanna do manipulate data on method test then throw back the result to this ajax. but I have an error when I just try to throw sid

var sid = jQuery(this).attr('id');
    console.log(sid);
    $.ajax({
        url: "TryJSON.aspx/test",
        type: "POST",
        data: JSON.stringify({ 'noSeat': sid }),
        contentType: "application/json; charset=utf-8",
        success: function (response) {
            var arr = JSON.parse(response.d);
            console.log(arr);
        },
        error: function () {
            alert("sorry, there was a problem!");
            console.log("error");
        },
        complete: function () {
            console.log("completed");
        }

    });

this is my C# code to receive noSeat

[WebMethod]
    [ScriptMethod(UseHttpGet = true)]
    public static string test(string noSeat)
    {
       // return noSeat;
        //JavaScriptSerializer serializer = new JavaScriptSerializer();
       // return new JavaScriptSerializer().Serialize(new { noSeat = noSeat });
    }

I have try return only noSeat and also with Javascript serializer. but it has an error. it says

An attempt was made to call the method 'test' using a POST request, which is not allowed.

I have been tried

return "Success !!"

but it doesn't appear on console and still same error. what's the matter ?

Answer 1

var sid = jQuery(this).attr('id');
console.log(sid);
$.ajax({
    url: "TryJSON.aspx/test",
    type: "POST",
    data: JSON.stringify({ 'noSeat': sid }),
    contentType: "application/json; charset=utf-8",
    dataType:'json',
    success: function (response) {
        var arr = JSON.parse(response.d);
        console.log(arr);
    },
    error: function () {
        alert("sorry, there was a problem!");
        console.log("error");
    },
    complete: function () {
        console.log("completed");
    }

});