老师好,下面代码运行报错,提示:未将对象引用设置到对象的实例。请问老师如何更改。谢谢!
Dim Productionchart As DataTable=DataTables("ProjectListAll")
Dim drProductionChart As DataRow
Dim Chart As WinForm.Chart '定义一个图表变量
Dim Series As WinForm.ChartSeries '定义一个图系变量
Dim t As Table = Tables("ProjectListAll") '定义一个变量t引用数据表
Chart = Forms("Data View").Controls("Productionchart") ' 引用窗口中的图表
Chart.ChartType = ChartTypeEnum.Bar '图表类型改为Bar(条形)
Chart.DataSource ="ProjectListAll" '设置绑定表
Chart.SeriesList.Clear() '清除图表原来的图系
Dim ChartDate As String=e.sender.value
messagebox.show("ok")
For Each c As Col In t.Cols
If drProductionChart("Date")=e.sender.value And drProductionChart("Block")=selectednodename And drProductionChart("Type")="2D"
Series = Chart.SeriesList.Add() '增加一个图系
Series.Text = c.Name '设置图系的标题
Series.X.DataField = "Date" 'X轴绑定到日期列
Series.Y.DataField = "T2D_PrimeProduction" '设置Y轴的绑定列
End If
If drProductionChart("Date")=e.sender.value And drProductionChart("Block")=selectednodename And drProductionChart("Type")="3D"
Series = Chart.SeriesList.Add() '增加一个图系
Series.Text = c.Name '设置图系的标题
Series.X.DataField = "Date" 'X轴绑定到日期列
Series.Y.DataField = "T3D_PrimeProduction" '设置Y轴的绑定列
End If
Next
Chart.VisualEffect = True '加上这一行,让你的图表更漂亮
Chart.LegendVisible = True '显示图列
Chart.LegendCompass= CompassEnum.South '图列显示在南方(底端)