使用vb.net创建三维饼图

我试图创建一个三维饼图，但出现了一个错误 这里是我使用的代码

Public Sub ShowChart(ByVal mylist As List(Of Classdayhag))
        Dim celltable As excel.Range
        Dim indexcol As Integer
        Dim indexrow As Integer
        Try

            With xlworksheet
                celltable = .Range("A1", "B" & (mylist.Count - 1))
                indexcol = 1
                indexrow = 1
                For Each item As Classdayhag In mylist
                    .Cells(indexrow, indexcol) = item.dayname
                    .Cells(indexrow, indexcol + 1) = item.count
                    indexrow += 1
                Next
                celltable.Select()
                Dim mychart As New excel.Chart
                With mychart
                    .Shapes.AddChart.Select()
                    .ChartType = excel.XlChartType.xl3DPie
                    .SetSourceData(Source:=celltable)
                    .ApplyLayout(6)
                End With
            End With

            objexcel.Visible = True
            RaiseEvent isshown()
            objexcel = Nothing
        Catch ex As Exception
            MessageBox.Show(ex.Message)
            objexcel = Nothing
        End Try

    End Sub

无法将“Microsoft.Office.Interop.Excel.ChartClass”类型的COM对象强制转换为“Microsoft.Office.Interop.Excel”类型的接口时出错。\u 在第一线升起

 .Shapes.AddChart.Select()

提前谢谢我成功了

Public Sub ShowChart(ByVal mylist As List(Of Classdayhag), ByVal title As String)

        'create chart

        Dim xlCharts As excel.ChartObjects
        Dim myChart As excel.ChartObject
        Dim celltable As excel.Range
        Dim indexcol As Integer
        Dim indexrow As Integer

        Try
            xlCharts = CType(xlworksheet.ChartObjects, excel.ChartObjects)
            myChart = xlCharts.Add(10, 80, 400, 400)
            With xlworksheet
                celltable = .Range("A1", "B" & (mylist.Count))


                indexcol = 1
                indexrow = 1
                For Each item As Classdayhag In mylist
                    .Cells(indexrow, indexcol) = item.dayname
                    .Cells(indexrow, indexcol + 1) = item.count
                    indexrow += 1
                Next
                celltable.Select()


                With myChart
                    .Chart.ChartType = excel.XlChartType.xl3DPie
                    .Chart.HasTitle = True
                    .Chart.ChartTitle.Text = title
                    .Chart.ChartTitle.Font.Name = "Arial"
                    .Chart.ChartTitle.Font.Size = 12
                    .Chart.ChartTitle.Font.Bold = True
                    .Chart.SetSourceData(Source:=celltable)
                    .Chart.ApplyLayout(6)

                End With
            End With

            objexcel.Visible = True
            RaiseEvent isshown()
            objexcel = Nothing
        Catch ex As Exception
            MessageBox.Show(ex.Message)
            objexcel = Nothing
        End Try

    End Sub