2

请参见以下示例：

<Window 
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:src="clr-namespace:WpfApplication1"
  SizeToContent="WidthAndHeight">
  <Window.DataContext>
    <src:CodeName/>
  </Window.DataContext>
  <TextBox Text="{Binding Code, UpdateSourceTrigger=PropertyChanged}" />
</Window>

Imports System.ComponentModel
Public Class CodeName
  Implements INotifyPropertyChanged

  Private m_Code As String
  Public Property Code() As String
    Get
      Return m_Code
    End Get
    Set(ByVal value As String)
      If Not String.IsNullOrWhiteSpace(value) Then value = "_" & value
      m_Code = value
      RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs("Code"))
    End Set
  End Property

  Public Event PropertyChanged(ByVal sender As Object,
    ByVal e As PropertyChangedEventArgs) _
      Implements INotifyPropertyChanged.PropertyChanged
End Class

如您所见，我正在更改已编辑的值，以便当用户在 中输入文本时，它会在其开头TextBox添加 a 进行更新。_

发生的情况是，当我在中键入123456789结果时TextBox：_________987654321不是_________123456789预期的那样。

有什么好的方法可以解决它？
我不想让我的整个代码被 KeyUp 等事件弄脏，移动插入符号。
另一方面，我确实希望在实体级别完成此操作。

注意：我的“现实生活”功能是用破折号格式化电话号码等。

4

2 回答 2

0 
Public Class TextBoxBehavor
Public Shared Function GetMoveCaretOnTextChange(ByVal element As TextBox) As Boolean
  If element Is Nothing Then Throw New ArgumentNullException("element")
  Return element.GetValue(MoveCaretOnTextChangeProperty)
End Function
Public Shared Sub SetMoveCaretOnTextChange(ByVal element As TextBox, ByVal value As Boolean)
  If element Is Nothing Then Throw New ArgumentNullException("element")
  element.SetValue(MoveCaretOnTextChangeProperty, value)
End Sub
Public Shared ReadOnly MoveCaretOnTextChangeProperty As DependencyProperty =
  DependencyProperty.RegisterAttached("MoveCaretOnTextChange",
    GetType(Boolean), GetType(TextBoxBehavior),
    New FrameworkPropertyMetadata(
      New PropertyChangedCallback(AddressOf MoveCaretOnTextChange_PropertyChanged)))

Private Shared Sub MoveCaretOnTextChange_PropertyChanged(ByVal sender As Object,
  ByVal e As DependencyPropertyChangedEventArgs)
  Dim tb = DirectCast(sender, TextBox)
  Static tb_TextChanged As TextChangedEventHandler =
    Sub(obj, tcea)
      Dim textBox = DirectCast(obj, TextBox)
      textBox.CaretIndex = textBox.Text.Length
    End Sub

  If CBool(e.NewValue) Then
    AddHandler tb.TextChanged, tb_TextChanged
  Else
    RemoveHandler tb.TextChanged, tb_TextChanged
  End If
End Sub
End Class

用法：

<TextBox src:TextBoxBehavior.MoveCaretOnTextChange="True"
  xmlns:src="clr-namespace:WpfApplication1" />
于 2010-12-17T10:32:15.653 回答
0

我会使用文本框的 textchanged 事件将插入符号移到末尾，如下所示：

 <TextBox Name="textBox1" Text="{Binding Code, UpdateSourceTrigger=PropertyChanged}" TextChanged="textChangedEventHandler"/>


Private Sub textChangedEventHandler(ByVal sender As Object, ByVal args As TextChangedEventArgs)
   textBox1.CaretIndex = textBox1.Text.Length
End Sub
于 2010-12-17T08:39:22.033 回答