无法在ASPX，500的ChartJS中显示数据（内部服务器错误）

Question

实际上，我是ASP的新手，我正尝试在ChartJS中显示mySql数据库中的一些数据，为了进行测试，我制作了一个简单的表，其中包含3行，该行具有2011年和2月。显示该年份和月份的数量。

问题是，当我运行网站时，我得到500（内部服务器错误），但是问题是，如果我在方法中设置了断点，则该方法在asmx文件中甚至无法到达该站点。

这是我的webservice.asmx代码：

<System.Web.Services.WebService(Namespace:="http://tempuri.org/")> _
<System.Web.Services.WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
<ToolboxItem(False)> _
Public Class webservice
    Inherits System.Web.Services.WebService
    Dim SQLConnect As String = ConfigurationManager.ConnectionStrings("myConnectionString").ConnectionString

    <WebMethod()>
    Public Function getTrafficSourceData(ByVal gData As List(Of String)) As List(Of trafficSourceData)
        Dim t As List(Of trafficSourceData) = New List(Of trafficSourceData)()
        Dim arrColor As String() = New String() {"#231F20", "#FFC200", "#F44937", "#16F27E", "#FC9775", "#5A69A6"}

        Using cn As MySqlConnection = New MySqlConnection(SQLConnect)
            Dim myQuery As String = "select * from statistica where anno =@year and mese=@month"
            Dim cmd As MySqlCommand = New MySqlCommand()
            cmd.CommandText = myQuery
            cmd.CommandType = CommandType.Text
            cmd.Parameters.AddWithValue("@year", gData(0))
            cmd.Parameters.AddWithValue("@month", gData(1))
            cmd.Connection = cn
            cn.Open()
            Dim dr As MySqlDataReader = cmd.ExecuteReader()

            If dr.HasRows Then
                Dim counter As Integer = 0

                While dr.Read()
                    Dim tsData As trafficSourceData = New trafficSourceData()
                    tsData.value = dr("quantita").ToString()
                    tsData.label = dr("nomeprodotto").ToString()
                    tsData.color = arrColor(counter)
                    t.Add(tsData)
                    counter += 1
                End While
            End If
        End Using

        Return t
    End Function
Public Class trafficSourceData
    Public Property label As String
    Public Property value As String
    Public Property color As String
    Public Property hightlight As String
End Class

结束班级

这是JQuery代码

$(document).ready(function () {
        var gData = [];
        gData[0] = "2011";
        gData[1] = "FEBBRAIO";

        var jsonData = JSON.stringify({
            gData: gData
        });
        $.ajax({
            type: "POST",
            url: "webservice.asmx/getTrafficSourceData",
            data: jsonData,
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: OnSuccess_,
            error: OnErrorCall_
        });

        function OnSuccess_(response) {
            var aData = response.d;
            var arr = [];
            $.each(aData, function (inx, val) {
                var obj = {};
                obj.color = val.color;
                obj.value = val.value;
                obj.label = val.label;
                arr.push(obj);
            });
            var ctx = $("#chartMensile").get(0).getContext("2d");
            var myPieChart = new Chart(ctx).Pie(arr);
        }

    function OnErrorCall_(response) {
        alert("ERRORE!");
    }

});