WPF textbox limits two ways to enter numbers only

MainWindow.xaml:

<Window x:Class="wpfcore.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:wpfcore" 
        xmlns:controls="http://metro.mahapps.com/winfx/xaml/controls"
        mc:Ignorable="d"
        Background="#2D2D30"
        SnapsToDevicePixels="True"
        FontSize="18"
        UseLayoutRounding="True"
        Title="MainWindow" Width="820" Height="340">
    <StackPanel>
        <!-- The first method , Set disable input method directly , And add PreviewTextInput event , If you don't do that , No input -->
        <TextBox InputMethod.IsInputMethodEnabled="False" PreviewTextInput="TextBox_PreviewTextInput" Margin="10"/>
        <!-- The second method , Write an additional attribute , When properties change , to textbox Add the corresponding event , When this is finished , It is convenient to reuse -->
        <TextBox local:TextBoxAttachedProperties.IsOnlyNumber="true" Margin="10"/>
    </StackPanel>
</Window>

MainWindow.cs:

using System.Text.RegularExpressions;
using System.Windows;

namespace wpfcore
{
    
    public partial class MainWindow : Window
    {
    
        public MainWindow()
        {
    
            InitializeComponent();
            DataContext = this;

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

}

The second method ：
Create a new one TextBoxAttachedProperties.cs file , Define additional properties ：

using System.Text.RegularExpressions;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;

namespace wpfcore
{
    
    public class TextBoxAttachedProperties
    {
    
        public static bool GetIsOnlyNumber(DependencyObject obj)
        {
    
            return (bool)obj.GetValue(IsOnlyNumberProperty);
        }
        public static void SetIsOnlyNumber(DependencyObject obj, bool value)
        {
    
            obj.SetValue(IsOnlyNumberProperty, value);
        }
        public static readonly DependencyProperty IsOnlyNumberProperty =
            DependencyProperty.RegisterAttached("IsOnlyNumber", typeof(bool), typeof(TextBox), new PropertyMetadata(false,
                (s, e) =>
                {
    
                    if (s is TextBox textBox)
                    {
    
                        textBox.SetValue(InputMethod.IsInputMethodEnabledProperty, !(bool)e.NewValue);
                        textBox.PreviewTextInput -= TxtInput;
                        if (!(bool)e.NewValue)
                        {
    
                            textBox.PreviewTextInput += TxtInput;
                        }
                    }
                }));
        private static void TxtInput(object sender, System.Windows.Input.TextCompositionEventArgs e)
        {
    
            e.Handled = new Regex("[^0-9]+").IsMatch(e.Text);
        }
    }
}