WPF文本框中仅包含字母字符

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

namespace WpfApp
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void TextBox_PreviewTextInput(object sender, TextCompositionEventArgs e)
        {
            // 使用正则表达式验证输入是否为字母
            Regex regex = new Regex("^[a-zA-Z]+$");
            e.Handled = !regex.IsMatch(e.Text);
        }
    }
}