WPF中禁止输入和粘贴非数值字符

控件TextBox，相关事件KeyDown、TextChanged，事件处理函数如下:

private void textBox1_KeyDown(object sender, KeyEventArgs e)
        {
            TextBox txt = sender as TextBox;

            //屏蔽非法按键
            if ((e.Key >= Key.NumPad0 && e.Key <= Key.NumPad9) || e.Key == Key.Decimal || e.Key.ToString() == "Tab" || e.Key == Key.Subtract)
            {
                if ((txt.Text.Contains(".") && e.Key == Key.Decimal) || (txt.Text.Contains("-") && e.Key == Key.Subtract))
                {
                    e.Handled = true;
                    return;
                }
                e.Handled = false;
            }
            else if (((e.Key >= Key.D0 && e.Key <= Key.D9) || e.Key == Key.OemPeriod || e.Key == Key.OemMinus) && e.KeyboardDevice.Modifiers != ModifierKeys.Shift)
            {
                if ((txt.Text.Contains(".") && e.Key == Key.OemPeriod) || (txt.Text.Contains("-") && e.Key == Key.OemMinus))
                {
                    e.Handled = true;
                    return;
                }
                e.Handled = false;
            }
            else
            {
                e.Handled = true;
            }
        }

        private void textBox1_TextChanged(object sender, TextChangedEventArgs e)
        {
            if (textBox1.Text.Length == 1 && textBox1.Text == "-")
                e.Handled = true;
            else
            {
                //屏蔽中文输入和非法字符粘贴输入
                TextBox textBox = sender as TextBox;
                TextChange[] change = new TextChange[e.Changes.Count];
                e.Changes.CopyTo(change, 0);

                int offset = change[0].Offset;
                if (change[0].AddedLength > 0)
                {
                    double num = 0;
                    if (!Double.TryParse(textBox.Text, out num))
                    {
                        textBox.Text = textBox.Text.Remove(offset, change[0].AddedLength);
                        textBox.Select(offset, 0);
                    }
                }
            }
        }

以上内容来自http://www.cnblogs.com/midcn/archive/2011/03/14/1983818.html，稍的改动.