System.Net.Mail创建无效的电子邮件和eml文件？在主机名中插入额外的点

using System.Net.Mail;

// 创建一个无效的电子邮件地址
string invalidEmailAddress = "example.com";

// 创建一个邮件对象
MailMessage mailMessage = new MailMessage();

// 设置发件人地址
mailMessage.From = new MailAddress("sender@example.com");

// 设置收件人地址
mailMessage.To.Add(invalidEmailAddress);

// 设置邮件主题和正文
mailMessage.Subject = "Test Email";
mailMessage.Body = "This is a test email.";

using System.IO;

// 创建一个文件流
FileStream fileStream = new FileStream("invalid_email.eml", FileMode.Create);

// 创建一个SmtpClient对象
SmtpClient smtpClient = new SmtpClient();

// 将邮件对象序列化为eml文件
smtpClient.PickupDirectoryLocation = "invalid_email.eml";
smtpClient.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory;
smtpClient.Send(mailMessage);

// 关闭文件流
fileStream.Close();