Javascript没有在检索json数据后填充图表

Question

我有一个div来处理图表<div id="LineSumbalance"></div>和textbox以使关键参数button触发。

<asp:TextBox ID="txtDate" CssClass="form-control" runat="server"></asp:TextBox> 
<asp:TextBox ID="txtSearchTerm" runat="server" Width="200px" class="form-control" placeholder="Terminal Number" spellcheck="false"></asp:TextBox> 
<asp:Button ID="btnSearchTerm" runat="server" Text="Search" class="btn btn-primary" /> 

我写后面的代码从数据库中查询数据：

<WebMethod()> 
Public Shared Function GetChart(ByVal Tdate As String, ByVal Term As String) As List(Of Object) 
    Dim BizFunc As New BizFunction.UtilFormat 
    Dim chartData As New List(Of Object)() 

    Dim TabName As String = "TA" & Tdate 
    Dim TodayDate As String = BizFunc.Date2YYMM(Today.Date) 
    Dim labels As New List(Of String)() 
    If Tdate = Mid(TodayDate, 1, 4) Then 
     TabName = "(select * from " & TabName & " union all select * from TA" & TodayDate & ") TA " 
    End If 
    Dim query As String = "WITH t1 AS (SELECT dt,DATEADD(MONTH,DATEDIFF(MONTH,'1900-01-01',dt),'1900-01-01') AS firstInMonth,DATEADD(DAY,-1,DATEADD(MONTH,DATEDIFF(MONTH,'1900-01-01',dt)+1,'1900-01-01')) AS lastInMonth,amount " & 
     " FROM(SELECT CONVERT(DATE, tran_date) AS dt,COUNT(*) AS AMOUNT FROM " & TabName & " WHERE TERM Like '%" & Term.PadRight(16, " ") & "%' and (TRANS = '05' or TRANS = '06') GROUP BY TRAN_DATE) AS st " & 
     "Group BY dt, amount), " & 
     "Calendar " & 
     " AS (SELECT DISTINCT DATEADD(DAY, c.number,t1.firstInMonth) AS d FROM t1 JOIN master..spt_values AS c On type = 'P' AND DATEADD(DAY,c.number,t1.firstInMonth) BETWEEN t1.firstInMonth AND t1.lastInMonth) " & 
     " Select DatePart(dd, d) Date, Case When amount Is NULL Then 0 Else amount End As amount FROM calendar As c LEFT JOIN t1 On t1.dt = c.d;" 
    Dim dtbal As DataTable = GetData(query) 

    Dim series1 As New List(Of Integer)() 

    For Each row As DataRow In dtbal.Rows 
     labels.Add(Convert.ToString(row("Date"))) 
    Next 
    chartData.Add(labels) 
    For Each row As DataRow In dtbal.Rows 
     series1.Add(Convert.ToInt32(row("AMOUNT"))) 

    Next 
    chartData.Add(series1) 
    Return chartData 
End Function 

上面的代码是完美的工作。

的问题是Javascript：

$(function() { 
$("[id*=btnSearchTerm]").click(function() { 
     LoadChart(); 
    }); 
}); 
function LoadChart() { 
    var tdate = $("[id*=txtdate]").val(); 
    var term = $("[id*=txtSearchTerm]").val(); 

    $.ajax({ 
     type: "POST", 
     url: "MonthlyBalancing.aspx/GetChart", 
     data: "{TDate: '" + tdate + "', term: '" + term + "'}", 
     contentType: "application/json; charset=utf-8", 
     dataType: "json", 
     success: function (r) { 
      var labels = r.d[0]; 
      var series1 = r.d[1]; 
       var data = { 
       labels: labels, 
       datasets: [ 
        { 
         label: "Dataset1", 
         backgroundColor: "rgba(38, 185, 154, 0.31)", 
         borderColor: "rgba(38, 185, 154, 0.7)", 
         pointBorderColor: "rgba(38, 185, 154, 0.7)", 
         pointBackgroundColor: "rgba(38, 185, 154, 0.7)", 
         pointHoverBackgroundColor: "#fff", 
         pointHoverBorderColor: "rgba(220,220,220,1)", 
         pointBorderWidth: 1, 
         data: series1 
        }] 
      }; 

       $("#LineSumbalance").html(""); 
      var canvas = document.createElement('canvas'); 
      $("#LineSumbalance")[0].appendChild(canvas); 

      //Fix for IE 8 
      if ($.browser.msie && $.browser.version == "8.0") { 
       G_vmlCanvasManager.initElement(canvas); 
      } 
      var ctx = canvas.getContext('2d'); 
        var lineChart = new Chart(ctx).Line(data, { 
       bezierCurve: false 
        }); 

     }, 
     failure: function (response) { 
      alert('There was an error.'); 
     } 
    }); 
} 

我尝试每一行提醒上它停留在$.Ajax。即使失败也不会执行任何事情。

Answer 1

命名至少有一个问题：您的控件是<asp:TextBox ID="txtDate"，但您拨打$("[id*=txtdate]").val();，似乎也需要txtDate（大写D）。

关于ajax - 您需要调试该函数以确保它在每一步中获得的内容。在需要的地方添加debugger;或alert();并运行代码。例如，添加

... 
success: function (r) { 
    alert(r); 
    var labels = r.d[0]; 
... 

并查看r是否将被定义。