Question

我正在尝试使用现有的System.Net.Mail.SmtpClient创建自定义smtp类，但不知何故它没有获取在类外部设置的属性值。

Public Class CustomClient
   Implements IDisposable

   Private smtpClient As System.Net.Mail.SmtpClient

   Public Property FromAddress As String
   Public Property ToAddress As String
   Public Property Subject As String
   Public Property Body As String
   Public Property MtaIP As String

   Public Sub New()

      Me.smtpClient = New Net.Mail.SmtpClient(MtaIP, 25) 'SmtpClient's Host field is still empty after initializationa
      smtpClient.EnableSsl = False
      smtpClient.UseDefaultCredentials = True
      smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network
   End Sub

   Public Sub SendMessage()
     Try
        Using message As New MailMessage(FromAddress, ToAddress)

            message.Subject = Subject
            message.Body = "TEST"
            message.BodyTransferEncoding = Net.Mime.TransferEncoding.QuotedPrintable
            smtpClient.Send(message)
        End Using
     Catch ex As Exception
        Dim errorMsg As String = " SMTPClient encountered the following error..." &
               vbNewLine & vbNewLine & "Exception Information:" & vbNewLine & BuildExceptionReport(ex)
        CourierShared.Common.sendMessage(errorMsg, MessageTypes.Failure)
    End Try
  End Sub

End Class

以上是我的代码。我确认MtaIP的值是从外部正确传递的，但不知何故它抛出异常抱怨主机名未指定。当我将属性更改为公共字段而手动分配值时，它可以正常工作。

我遗失了一些有财产用途的东西吗？

编辑：我在CustomClient对象中添加了更具体的send方法，下面是我如何使用该类发送消息

Public Class CustomClientTest
  Public Sub Test()
     Using client As New CustomClient()
         client.FromAddress = inboundSender
         client.ToAddress = inboundRecipient
         client.Subject = inboundMsgSubject
         client.MtaIP = "123.234.34.56" 'I use actual host that works but put this as a reference
         client.SendMessage()
     End Using
  End Sub
End Class

Answer 1

您的属性没有Get和/或Set方法。例如：

Private mFromAddress as string

Public Property FromAddress () As String
    Get
        FromAddress = mFromAddress 
    End Get
    Set(ByVal value As String)
        mFromAddress = value
    End Set
End Property

在您的外部代码中，首先实例化该类：

Dim MySMTPClient as  SMTPClient
' Now you can set the property
MySMTPClient.FromAddress = "SomeEmailAddress"

无法将属性值传递给私有对象的构造函数

1 个答案: