我有一个带有绑定DGV的表。该表有12列，其中一列是复选框。该表中包含数据，没有任何问题。
我想清除表格，然后从Excel将数据导入表格。 问题是我清除表并发生异常。这是因为复选框具有空值。
其他表没有问题，没有复选框。我可以清除表格并从Excel导入数据。
Try ... Catch程序甚至没有发现错误。
＆＃39;清除DGV
尝试
DsAstroCatalogueData.tblMessierData.Clear（）
赶上前例外
MessageBox.Show（ex.Message，Me.Text，MessageBoxButtons.OK，MessageBoxIcon.Error）
最后
＆＃39;没有
结束尝试
完整代码：
Private Sub MnuImportFromExcel_Click(sender As Object, e As EventArgs) Handles mnuImportFromExcel.Click
Dim strExcelFilePath As String = ""
Dim strCellValue As String = ""
Dim strColumn1 As String = ""
Dim strColumn2 As String = ""
Dim strColumn3 As String = ""
Dim strColumn4 As String = ""
Dim strColumn5 As String = ""
Dim strColumn6 As String = ""
Dim strColumn7 As String = ""
Dim strColumn8 As String = ""
Dim strColumn9 As String = ""
Dim strColumn10 As String = ""
Dim boolColumn11 As Boolean = False
Dim strColumn12 As String = ""
Dim intColumnIndex As Integer = 0
Dim intRowIndex As Integer = 0
Dim intItemsAddedCount As Integer = 0
statusCatalogProgressBar.Value = 0
Try
'Select Excel File
With OpenFileDialogExcel()
.Filter = "Excel Files|*.xls;*.xlsx"
.Title = "Select- Excel Configuration File"
.FileName = ""
End With
If (OpenFileDialogExcel.ShowDialog() = DialogResult.OK) Then
strExcelFilePath = OpenFileDialogExcel.FileName
Else
strExcelFilePath = ""
End If
Catch ex As Exception
MessageBox.Show(ex.Message, Me.Text, MessageBoxButtons.OK, MessageBoxIcon.Error)
Finally
'Nothing
End Try
If strExcelFilePath IsNot "" Then
'Update Status Bar Text
statusCatalogFrm.Text = "Importing Catalog from Excel..."
statusCatalogProgressBar.Visible = True
statusCatalogRightLabel.Visible = False
Dim xlAppEyepieces As New Excel.Application
Dim xlWorkBookEyepieces As Excel.Workbook
Dim xlWorkSheetEyepieces As Excel.Worksheet
Dim xlRangeEyepieces As Excel.Range
Try
' Open Excel Spreadsheet.
xlWorkBookEyepieces = xlAppEyepieces.Workbooks.Open(strExcelFilePath)
' Loop over all sheets.
For i As Integer = 1 To xlWorkBookEyepieces.Sheets.Count
' Get Worsheet Data.
xlWorkSheetEyepieces = CType(xlWorkBookEyepieces.Sheets(i), Worksheet)
' Get Data Range.
xlRangeEyepieces = xlWorkSheetEyepieces.UsedRange
' Load all cells into 2d array.
Dim objExcelArray(,) As Object = CType(xlRangeEyepieces.Value(XlRangeValueDataType.xlRangeValueDefault), Object(,))
'Close COM Objects
System.Runtime.InteropServices.Marshal.ReleaseComObject(xlRangeEyepieces)
System.Runtime.InteropServices.Marshal.ReleaseComObject(xlWorkSheetEyepieces)
ReleaseObject(xlRangeEyepieces)
ReleaseObject(xlWorkSheetEyepieces)
' Scan the cells.
'If objExcelArray IsNot Nothing Then
' Get bounds of the array.
Dim NumberOfRows As Integer = objExcelArray.GetUpperBound(0) 'Rows
Dim NumberOfColumns As Integer = objExcelArray.GetUpperBound(1) 'Columns
'Progress Bar Maximum Value
statusCatalogProgressBar.Maximum = NumberOfRows
'Clear DGV
Try
DsAstroCatalogueData.tblMessierData.Clear()
Catch ex As Exception
MessageBox.Show(ex.Message, Me.Text, MessageBoxButtons.OK, MessageBoxIcon.Error)
Finally
'Nothing
End Try
' Loop over all elements.
For intRowIndex = 0 To NumberOfRows - 2
For intColumnIndex = 1 To NumberOfColumns
Try
'Test for NULL Value
If objExcelArray(intRowIndex + 2, intColumnIndex) IsNot Nothing Then
strCellValue = objExcelArray(intRowIndex + 2, intColumnIndex).ToString
Select Case intColumnIndex
Case 1
strColumn1 = strCellValue
Case 2
strColumn2 = strCellValue
Case 3
strColumn3 = strCellValue
Case 4
strColumn4 = strCellValue
Case 5
strColumn5 = strCellValue
Case 6
strColumn6 = strCellValue
Case 7
strColumn7 = strCellValue
Case 8
strColumn8 = strCellValue
Case 9
strColumn9 = strCellValue
Case 10
strColumn10 = strCellValue
Case 11
boolColumn11 = False
Case 12
strColumn12 = strCellValue
End Select
Else
Select Case intColumnIndex
Case 1
strColumn1 = ""
Case 2
strColumn2 = ""
Case 3
strColumn3 = ""
Case 4
strColumn4 = ""
Case 5
strColumn5 = ""
Case 6
strColumn6 = ""
Case 7
strColumn7 = ""
Case 8
strColumn8 = ""
Case 9
strColumn9 = ""
Case 10
strColumn10 = ""
Case 11
boolColumn11 = False
Case 12
strColumn1 = ""
End Select
End If
Catch ex As Exception
MessageBox.Show(ex.Message, Me.Text, MessageBoxButtons.OK, MessageBoxIcon.Error)
Finally
'Nothing
End Try
Next
'Add data to Data Table
'If (strColumn1 IsNot "") And (strColumn2) IsNot "" Then
With DsAstroCatalogueData
.Tables("tblMessierData").Rows.Add()
.Tables("tblMessierData").Rows(intRowIndex).Item("NGC") = strColumn1
.Tables("tblMessierData").Rows(intRowIndex).Item("Messier") = strColumn2
.Tables("tblMessierData").Rows(intRowIndex).Item("ObjectType") = strColumn3
.Tables("tblMessierData").Rows(intRowIndex).Item("ObjectName") = strColumn4
.Tables("tblMessierData").Rows(intRowIndex).Item("Constellation") = strColumn5
.Tables("tblMessierData").Rows(intRowIndex).Item("Magnitude") = strColumn6
.Tables("tblMessierData").Rows(intRowIndex).Item("RightAscension") = strColumn7
.Tables("tblMessierData").Rows(intRowIndex).Item("Declination") = strColumn8
.Tables("tblMessierData").Rows(intRowIndex).Item("ObjectSize") = strColumn9
.Tables("tblMessierData").Rows(intRowIndex).Item("Comment") = strColumn10
.Tables("tblMessierData").Rows(intRowIndex).Item("Viewed") = boolColumn11
.Tables("tblMessierData").Rows(intRowIndex).Item("ImageFile") = strColumn12
End With
intItemsAddedCount = (intRowIndex + 1)
'Update Staus Bar
statusCatalogFrm.Text = "Importing Catalog from Excel... [" & intItemsAddedCount & " of " & (NumberOfRows - 1) & " rows]"
statusCatalogProgressBar.Value = intItemsAddedCount
StatusStripMessierFrm.Update()
'End If
strCellValue = ""
Next
'End If
Next
dgvMessierData.Refresh()
'Data Import Completed
MessageBox.Show("Data Import Complete" & vbLf & vbLf & intItemsAddedCount &
" items added", "AstroCompanion - Import Catalog Data from Exel",
MessageBoxButtons.OK, MessageBoxIcon.Information)
'Update Status Bar Text
statusCatalogFrm.Text = "Ready"
statusCatalogProgressBar.Value = 0
statusCatalogProgressBar.Visible = False
'Close all Excel items
xlAppEyepieces.Workbooks.Close()
xlAppEyepieces.Quit()
GC.Collect()
GC.WaitForPendingFinalizers()
System.Runtime.InteropServices.Marshal.ReleaseComObject(xlWorkBookEyepieces)
System.Runtime.InteropServices.Marshal.ReleaseComObject(xlAppEyepieces)
ReleaseObject(xlWorkBookEyepieces)
ReleaseObject(xlAppEyepieces)
Catch ex As Exception
MessageBox.Show(ex.Message, Me.Text, MessageBoxButtons.OK, MessageBoxIcon.Error)
Finally
GC.Collect()
End Try
End If
End Sub