我使用了一些已经在这里的东西，并使用一个行为把我自己的扭曲，这样我就不必在大量的视图中传播这段代码……

public class AllowableCharactersTextBoxBehavior : Behavior<TextBox>
{
    public static readonly DependencyProperty RegularExpressionProperty =
         DependencyProperty.Register("RegularExpression", typeof(string), typeof(AllowableCharactersTextBoxBehavior),
         new FrameworkPropertyMetadata(".*"));
    public string RegularExpression
    {
        get
        {
            return (string)base.GetValue(RegularExpressionProperty);
        }
        set
        {
            base.SetValue(RegularExpressionProperty, value);
        }
    }

    public static readonly DependencyProperty MaxLengthProperty =
        DependencyProperty.Register("MaxLength", typeof(int), typeof(AllowableCharactersTextBoxBehavior),
        new FrameworkPropertyMetadata(int.MinValue));
    public int MaxLength
    {
        get
        {
            return (int)base.GetValue(MaxLengthProperty);
        }
        set
        {
            base.SetValue(MaxLengthProperty, value);
        }
    }

    protected override void OnAttached()
    {
        base.OnAttached();
        AssociatedObject.PreviewTextInput += OnPreviewTextInput;
        DataObject.AddPastingHandler(AssociatedObject, OnPaste);
    }

    private void OnPaste(object sender, DataObjectPastingEventArgs e)
    {
        if (e.DataObject.GetDataPresent(DataFormats.Text))
        {
            string text = Convert.ToString(e.DataObject.GetData(DataFormats.Text));

            if (!IsValid(text, true))
            {
                e.CancelCommand();
            }
        }
        else
        {
            e.CancelCommand();
        }
    }

    void OnPreviewTextInput(object sender, System.Windows.Input.TextCompositionEventArgs e)
    {
        e.Handled = !IsValid(e.Text, false);
    }

    protected override void OnDetaching()
    {
        base.OnDetaching();
        AssociatedObject.PreviewTextInput -= OnPreviewTextInput;
        DataObject.RemovePastingHandler(AssociatedObject, OnPaste);
    }

    private bool IsValid(string newText, bool paste)
    {
        return !ExceedsMaxLength(newText, paste) && Regex.IsMatch(newText, RegularExpression);
    }

    private bool ExceedsMaxLength(string newText, bool paste)
    {
        if (MaxLength == 0) return false;

        return LengthOfModifiedText(newText, paste) > MaxLength;
    }

    private int LengthOfModifiedText(string newText, bool paste)
    {
        var countOfSelectedChars = this.AssociatedObject.SelectedText.Length;
        var caretIndex = this.AssociatedObject.CaretIndex;
        string text = this.AssociatedObject.Text;

        if (countOfSelectedChars > 0 || paste)
        {
            text = text.Remove(caretIndex, countOfSelectedChars);
            return text.Length + newText.Length;
        }
        else
        {
            var insert = Keyboard.IsKeyToggled(Key.Insert);

            return insert && caretIndex < text.Length ? text.Length : text.Length + newText.Length;
        }
    }
}

下面是相关的视图代码:

<TextBox MaxLength="50" TextWrapping="Wrap" MaxWidth="150" Margin="4"
 Text="{Binding Path=FileNameToPublish}" >
     <interactivity:Interaction.Behaviors>
         <v:AllowableCharactersTextBoxBehavior RegularExpression="^[0-9.\-]+$" MaxLength="50" />
     </interactivity:Interaction.Behaviors>
</TextBox>

我们可以对文本框更改事件进行验证。下面的实现可以防止除数字和一个小数点以外的按键输入。

private void textBoxNumeric_TextChanged(object sender, TextChangedEventArgs e) 
{         
      TextBox textBox = sender as TextBox;         
      Int32 selectionStart = textBox.SelectionStart;         
      Int32 selectionLength = textBox.SelectionLength;         
      String newText = String.Empty;         
      int count = 0;         
      foreach (Char c in textBox.Text.ToCharArray())         
      {             
         if (Char.IsDigit(c) || Char.IsControl(c) || (c == '.' && count == 0))             
         {                 
            newText += c;                 
            if (c == '.')                     
              count += 1;             
         }         
     }         
     textBox.Text = newText;         
     textBox.SelectionStart = selectionStart <= textBox.Text.Length ? selectionStart :        textBox.Text.Length;     
} 

添加一个验证规则，以便在文本更改时检查数据是否是数字，如果是，则允许继续处理，如果不是，则提示用户该字段中只接受数字数据。

请参阅Windows演示基础中的验证

e.Handled = (int)e.Key >= 43 || (int)e.Key <= 34;

在预览文本框的按键事件。

事件处理程序正在预览文本输入。在这里，正则表达式只在文本输入不是数字时才匹配文本输入，然后它就不会进入文本框。

如果只需要字母，则将正则表达式替换为[^a-zA-Z]。

XAML

<TextBox Name="NumberTextBox" PreviewTextInput="NumberValidationTextBox"/>

XAML.CS文件

using System.Text.RegularExpressions;
private void NumberValidationTextBox(object sender, TextCompositionEventArgs e)
{
    Regex regex = new Regex("[^0-9]+");
    e.Handled = regex.IsMatch(e.Text);
}

Use:

Private Sub DetailTextBox_PreviewTextInput( _
  ByVal sender As Object, _
  ByVal e As System.Windows.Input.TextCompositionEventArgs) _
  Handles DetailTextBox.PreviewTextInput

    If _IsANumber Then
        If Not Char.IsNumber(e.Text) Then
            e.Handled = True
        End If
    End If
End Sub