bluesailor散记

引用 using System.Text.RegularExpressions;

            string txtUserName = UserName.Text;
            Regex reg = new Regex(@"[a-z0-9_\u4e00-\u9fa5]{3,20}");
            if (!reg.IsMatch(txtUserName))
            {
                userLabel.Text = "用户名不可用";
                return;
            }