C# TextBox控件实现只能输入数字的方法

if (e.KeyChar == '.' && this.txbEnd.Text.IndexOf(".") != -1)
            {
                e.Handled = true;
            }

            if (!((e.KeyChar >= 48 && e.KeyChar <= 57) || e.KeyChar == '.' || e.KeyChar == 8))
            {
                e.Handled = true;
            }