使用System.Threading.ThreadPool时没有内容的电子邮件

Question

我遇到了一个奇怪的行为，试图使用Threading.ThreadPool发送电子邮件。

这已经工作了一年多了，但最近它已经声明要间歇地发送没有内容的电子邮件。收件人和主题都很好，但是，其余的电子邮件是空白的。没有什么改变了代码的明智之处（除了它运行的服务器的Windows更新）。

下面是我使用的代码 - 有没有人有我如何可以缩小问题发生的位置的建议？在将电子邮件重新发送给声称收到空白电子邮件的人时，他们可以很好地使用它 - 它使用与发送的第一个完全相同的代码。

子生成电子邮件：

Public Sub EmailConfirmation(email As String, 
           firstname As String, 
           details As String) 

     Try 


      Dim embody As String = GlobalHelper.emailBody 
      'static class which loads the email text at application load for use later. 
      'This is a point of concern because it's obviously where the embody text is 
      'is loaded, but the issue is intermittent and if there was a failure here surely 
      'it would be caught by the 'try...catch' and a log of the error created (which has 
      'never happened). I also ran an experiment for a while where if this string was 
      'empty then create a log entry. After receiving a complaint of a blank email 
      'no error log was found. 

      embody = Replace(embody, "[FirstName]", firstname) 
      embody = Replace(embody, "[DATA]", details) 


      'create the mail message 
      Dim mail As New MailMessage() 

      'set the addresses 
      mail.From = New MailAddress("myemail@mydomain.com", "My Display Name") 
      mail.To.Add(email) 
      mail.IsBodyHtml = True 

      'set the content 
      mail.Subject = "Email Subject!" 
      mail.Body = embody 


      AddEmailToThreadPool(mail) 

     Catch ex As Exception 

     'if there is an error it is logged here. 

     End Try 


    End Sub 

分，增加了线程池：

Private Sub AddEmailToThreadPool(email As MailMessage) 
     System.Threading.ThreadPool.QueueUserWorkItem(New System.Threading.WaitCallback(AddressOf sendEmail), email) 
    End Sub 

子发送电子邮件：

Private Sub sendEmail(stateinfo As Object) 

     Dim email As MailMessage = CType(stateinfo, MailMessage) 


     Try 

      'send the message 
      Dim smtp As New SmtpClient("mail.mydomain.com") 
      smtp.Send(email) 
     Catch ex As Exception 
      'error is logged here. 
     End Try 

    End Sub 

Answer 1

那么，修复不正确的doc类型声明后，我几乎没有在一个月内对空白电子邮件进行过一次投诉。虽然我不确定为什么，但我会假设这可以解决所有问题。

感谢您的所有输入/帮助。

Answer 2

我从MSDN复制MailMessage class

此类型的任何公共静态（Visual Basic中的Shared）成员都是线程安全的。任何实例成员不保证是线程安全的。