Question

我正在动态创建一些控件并将它们绑定到数据库：

'childElem is an XElement containing data for the control,
'dpBindingSource is the bindingSource Connected with the database
 Select Case cntrl.GetType
    Case GetType(TextBox)
      Dim txt As TextBox
      txt = DirectCast(cntrl, TextBox)
      txt.DataBindings.Add(New Binding("Text", dpBindingSource, childElem.Element("Col_Source").Value, True))
      AddHandler txt.TextChanged, AddressOf controlValueChanged

     Case GetType(ComboBox)
       Dim cbo As ComboBox
       cbo = DirectCast(cntrl, ComboBox)
       With cbo
         .DataSource = dt 'datatable to fill the combo
         .DisplayMember = childElem.Element("Display_Member").Value
         .ValueMember = childElem.Element("Value_Member").Value
         .DataBindings.Add(New Binding("SelectedValue",dpBindingSource, childElem.Element("Col_Source").Value , True))
       End with
       AddHandler cbo.SelectedIndexChanged, AddressOf controlValueChanged

   End Select

因此，当我尝试更新时，请检查dpBindingSource_BindingComplete。例如，如果文本框中的格式应该是数字，我会得到一个消息框：

  Private Sub dpBindingSource_BindingComplete(sender As Object, e As System.Windows.Forms.BindingCompleteEventArgs) Handles dpBindingSource.BindingComplete

    If Not e.BindingCompleteState = BindingCompleteState.Success Then
        MessageBox.Show(e.ErrorText)
    End If
  End Sub

我想要的是控件名称，如果这不可能，那么导致错误的数据库中的列名称。

Answer 1

我找到了解决方案：

MessageBox.Show("Error :" & e.ErrorText + vbCrLf & _
                        "Control : " & e.Binding.Control.Name.ToString + vbCrLf & _
                        "Field : " & e.Binding.BindingMemberInfo.BindingField.ToString + vbCrLf & _
                        "Info :" & e.Binding.BindableComponent.ToString + vbCrLf & _
                        "Correct Format :" & e.Exception.InnerException.TargetSite.DeclaringType.Name)

BindingCompleteState - 获取导致异常的字段

1 个答案: