Question

我有以下问题：

我写过很少发送电子邮件的控制台应用程序。它的行为方式如下：

当我在调试模式下运行此应用程序并逐步完成代码时，它会发送电子邮件;
当我在调试模式下运行此应用程序并且没有逐步完成代码时，最后一封电子邮件不会被发送;
当我构建应用程序并将其移动到服务器并为其创建任务时，最后一封电子邮件不会被发送;
当我从Windows资源管理器执行应用程序时（双击.exe文件），最后一封电子邮件无法发送;
当我从命令提示符执行应用程序时，它会发送所有电子邮件;

有趣的是，当我把thread.sleep（200）发送给所有电子邮件时！请注意，我在ASP应用程序中使用此代码，并始终发送所有邮件。如果邮件有附件，它总是被发送，即使它是队列中的最后一个（但这是另一个正常工作的应用程序）。

我使用的代码（邮件类）：

 Public Class Mailer

        ' Methods
        Public Sub SendMail()
            Dim mail As New MailMessage(Me.Sender, Me.To, Me.Subject, Me.Body)
            mail.IsBodyHtml = True
            If Not Me.CC.Trim.Equals("") Then
                mail.CC.Add(Me.CC)
            End If
            If Not Me.BCC.Trim.Equals("") Then
                mail.Bcc.Add(Me.BCC)
            End If
            Dim client As New SmtpClient(Me.MailServer)
            client.Credentials = New NetworkCredential(Me.Username, Me.Password)
            client.Send(mail)
            mail.Dispose()
        End Sub


        ' Properties
        Public Property Attachments As String
            Get
                Return Me._attachments
            End Get
            Set(ByVal value As String)
                Me._attachments = value
            End Set
        End Property

        Public Property BCC As String
            Get
                Return Me._BCC
            End Get
            Set(ByVal value As String)
                Me._BCC = value
            End Set
        End Property

        Public Property Body As String
            Get
                Return Me._body
            End Get
            Set(ByVal value As String)
                Me._body = value
            End Set
        End Property

        Public Property CC As String
            Get
                Return Me._CC
            End Get
            Set(ByVal value As String)
                Me._CC = value
            End Set
        End Property

        Public ReadOnly Property MailSent As Boolean
            Get
                Return Me._mailSent
            End Get
        End Property

        Public Property MailServer As String
            Get
                Return Me._mailServer
            End Get
            Set(ByVal value As String)
                Me._mailServer = value
            End Set
        End Property

        Public Property Password As String
            Get
                Return Me._password
            End Get
            Set(ByVal value As String)
                Me._password = value
            End Set
        End Property

        Public Property Sender As String
            Get
                Return Me._sender
            End Get
            Set(ByVal value As String)
                Me._sender = value
            End Set
        End Property

        Public Property Subject As String
            Get
                Return Me._subject
            End Get
            Set(ByVal value As String)
                Me._subject = value
            End Set
        End Property

        Public Property [To] As String
            Get
                Return Me._recepients
            End Get
            Set(ByVal value As String)
                Me._recepients = value
            End Set
        End Property

        Public Property Username As String
            Get
                Return Me._username
            End Get
            Set(ByVal value As String)
                Me._username = value
            End Set
        End Property


        ' Fields
        Private _attachments As String
        Private _BCC As String
        Private _body As String
        Private _CC As String
        Private _mailSent As Boolean
        Private _mailServer As String
        Private _password As String
        Private _recepients As String
        Private _sender As String
        Private _subject As String
        Private _username As String
    End Class

发送电子邮件的代码：

Do While rd.Read

    Dim m As New LinksMailer.Mailer

    m.MailServer = ConfigurationSettings.AppSettings.Item("mailServer")
    m.Username = ConfigurationSettings.AppSettings.Item("mailUsername")
    m.Password = ConfigurationSettings.AppSettings.Item("mailPassword")
    m.Sender = ConfigurationSettings.AppSettings.Item("sender")
    m.To = Conversions.ToString(rd.Item("Email"))
    m.CC = ConfigurationSettings.AppSettings.Item("Cc")
    m.BCC = ConfigurationSettings.AppSettings.Item("Bcc")
    m.Subject = "Some subject...."
    m.Body = "Some HTML body..."
    m.SendMail()

    ' when I add this line everything works!!!
    ' Threading.Thread.Sleep(200)
Loop

这里发生了什么???

Answer 1

我与之合作的开发人员负责每月向大型（100k +）用户群发送简报，并在每封邮件之间建立400毫秒的延迟。他这样做是为了防止邮件服务器自动将他列为垃圾邮件发送者。您可能遇到SendMail安全问题。你一次发送多少封电子邮件？他从试错中到达了400毫秒的数字。

Answer 2

即使这是迟到的回复，我希望它可以帮助下一位读者

 Dim inte  As Integer
 Dim ji As Integer
 Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click

        If Grid.Rows.Count > 0 Then
            Dim inte As Integer = Grid.Rows.Count
            inte = inte - 1
            For ji = 0 To inte
                Dim email As String = Grid.Rows(ji).Cells(4).Text
                sendmail(email)
            Next ji
        End If

    End Sub

此代码将能够将电子邮件发送到网格的最后一行希望如果不做道歉将会奏效

Answer 3

实际上，我不发送大量邮件（最多20个），而且大多数只发送一个。但我注意到，当应用程序需要发送一封邮件时，它不会被发送，如果需要发送3封邮件，只发送前两封等等。我不认为这是一个问题。

邮件控制台应用程序不发送最后一封邮件

3 个答案: