asp.net 谷歌图表问题我的项目

如何解决asp.net 谷歌图表问题我的项目

此代码不起作用。我该怎么办，请帮帮我，数据库没有问题，我找不到解决方案

WebMethod 有问题吗？我做了一切，但有些东西我看不到

我被困在这个，我的项目正在等待这个

非常感谢解决这个问题的朋友

[网络方法]

[ScriptMethod(UseHttpGet = true,ResponseFormat = ResponseFormat.Json)]


public static List<ChartDetails> GetPiechartData()
{

    List<ChartDetails> dataList = new List<ChartDetails>();

    string sConnString = "Data Source=.;Initial Catalog=deneme;Integrated Security=True";


    sqlConnection baglanti = new sqlConnection(sConnString);

    
        

        sqlCommand cmd = new sqlCommand("select begeni,kontrolid from yorum",baglanti);

        baglanti.open();

        sqlDataReader droku = cmd.ExecuteReader();

        while (droku.Read())
        {
            dataList.Add(new ChartDetails
            {
                kontrolid = droku["kontrolid"].ToString(),begeni = Convert.ToInt32(droku["begeni"]),});

        }

        return dataList;
    }

public class ChartDetails
{
    public string kontrolid { get; set; }
    public int begeni { get; set; }
}

<script type="text/javascript" src="https://www.google.com/jsapi"></script>   

  <script type="text/javascript">
      google.charts.load('current',{ packages: ['corechart'] });
      google.charts.setonLoadCallback(drawChart);

    
</script>

<script type="text/javascript">


    $(function () {
        $.ajax({
            type: "POST",dataType: "json",contentType: "application/json; charset=utf-8",url: "Default17.aspx/GetPiechartData",data: "{}",success: function (response) {                    
                drawchart(response.d);
            },error: function () {
                alert("Error loading data...........");
            }
        });
    })

  

    function drawchart(dataValues) {

        var data = new google.visualization.DataTable(); 

        data.addColumn('string','kontrolid');
        data.addColumn('number','begeni');

        for (var i = 0; i < dataValues.length; i++) {
            data.addRow([dataValues[i].kontrolid,dataValues[i].begeni]);
        }

        var options = {
            title: 'Company Performance',curveType: 'function',legend: { position: 'bottom' }
        };

        var chart = new google.visualization.LineChart(document.getElementById('curvechart'));

        chart.draw(data,options);
    }


</script>