这里有一个非常简单和容易的方法来做到这一点使用MVVM。

在视图模型中绑定一个整数属性的文本框，这将像宝石一样工作…它甚至会在文本框中输入非整数时显示验证。

XAML代码:

<TextBox x:Name="contactNoTxtBox"  Text="{Binding contactNo}" />

查看模型代码:

private long _contactNo;
public long contactNo
{
    get { return _contactNo; }
    set
    {
        if (value == _contactNo)
            return;
        _contactNo = value;
        OnPropertyChanged();
    }
}

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>

也可以简单地实现一个验证规则，并将其应用到TextBox:

  <TextBox>
    <TextBox.Text>
      <Binding Path="OnyDigitInput" Mode="TwoWay" UpdateSourceTrigger="PropertyChanged">
        <Binding.ValidationRules>
          <conv:OnlyDigitsValidationRule />
        </Binding.ValidationRules>
      </Binding>
    </TextBox.Text>

实现如下规则(使用与其他答案中建议的相同的Regex):

public class OnlyDigitsValidationRule : ValidationRule
{
    public override ValidationResult Validate(object value, CultureInfo cultureInfo)
    {
        var validationResult = new ValidationResult(true, null);

        if(value != null)
        {
            if (!string.IsNullOrEmpty(value.ToString()))
            {
                var regex = new Regex("[^0-9.-]+"); //regex that matches disallowed text
                var parsingOk = !regex.IsMatch(value.ToString());
                if (!parsingOk)
                {
                    validationResult = new ValidationResult(false, "Illegal Characters, Please Enter Numeric Value");
                }
            }
        }

        return validationResult;
    }
}

如果你不想写很多代码来做一个基本的函数(我不知道为什么人们要写很长的方法)，你可以这样做:

添加命名空间: 使用包含; 在XAML中，设置TextChanged属性: <TextBox x:Name="txt1" TextChanged="txt1_TextChanged"/> 在WPF的txt1_TextChanged方法下，添加Regex。替换: private void txt1_TextChanged(对象发送者，TextChangedEventArgs e) ｛ txt1。Text = Regex.Replace(txt1. replace)Text， "[^0-9]+"， ""); ｝

我允许数字键盘号码和退格:

    private void TextBox_PreviewKeyDown(object sender, KeyEventArgs e)
    {
        int key = (int)e.Key;

        e.Handled = !(key >= 34 && key <= 43 || 
                      key >= 74 && key <= 83 || 
                      key == 2);
    }

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