原创 C#下屏蔽非法字符编辑的方法代码

        private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
        {//与delphi一样的处理方法
            char ch = e.KeyChar;
            if (!((ch >= '0' && ch <= '9') || (ch >= 'a' && ch <= 'f') || (ch >= 'A' && ch <= 'F')))
            {
                switch (ch)
                {
                    case '\x08'://退格
                    case '\x0d'://回车
                        break;//放过
                    default:
                        e.KeyChar = '\x0';//放弃输入的非法字符
                        MessageBox.Show("请正确输入16进制数!!!", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                        break;
                }
            }
            else
            {//合法16进制数
                e.KeyChar |= ' ';//强制转换为小写字母
            }
        }