C#

hello

i want to edit a file by c# string by this code

                string text = File.ReadAllText(@"c:\a.txt", Encoding.UTF8);
                string text1 = text.Replace("xx", XX");
                File.WriteAllText(@"d:\a.txt", text1);

i want to search in string and when find example replace exam\ple and 4 word after exam\ple with exam\plexxxx

problem is i dont know what is the 4 word and i want replace.

i want any like * in windows seach.

in windows search * can support all character.

The specified string is not in the form required for an e-mail address.

 try
            {
                MailMessage mail = new MailMessage();
                SmtpClient SmtpServer = new SmtpClient(""smtp.gmail.com"");

                mail.From = new MailAddress(Config.username);
                mail.To.Add(Config.toEmail);
                mail.Subject = Config.subject; ;
                mail.Body = text;

                if (sendImage)
                {
                    var stream = new MemoryStream();
                    img.Save(stream, ImageFormat.Jpeg);
                    stream.Position = 0;
                    mail.Attachments.Add(new Attachment(stream, ""image / jpg""));
                }

                SmtpServer.Port = Config.smtpPort;
                SmtpServer.Credentials = new System.Net.NetworkCredential(Config.username, Config.password);
                SmtpServer.EnableSsl = true;

                SmtpServer.Send(mail);
Console.WriteLine(""Email has been sent!"");
            }
            catch (Exception e) { Console.WriteLine(e.Message); }