Visual Basic

sender.SendEmailCompleted += (o, eventArgs) 
  => Console.WriteLine(eventArgs.RetryCount);

AddHandler sender.SendEmailCompleted, Sub(ByVal sender As Object, ByVal e As SendEmailCompletedEventArgs)
    Console.WriteLine(eventArgs.RetryCount)
End Sub

Public Async Function SendEmailAsync(ByVal smtpClient As SmtpClient, ByVal message As MailMessage, ByVal retryCount As Integer) As Task(Of SendEmailCompletedEventArgs)
    Dim currentTry As Integer = 0
    While currentTry < retryCount
        Try
            Await smtpClient.SendMailAsync(message)
            Return New SendEmailCompletedEventArgs(Nothing, False, Nothing, currentTry)
            
        Catch exception As Exception
            currentTry += 1
            If currentTry >= retryCount Then
                Return New SendEmailCompletedEventArgs(ex, True, Nothing, currentTry)
            End If
        End Try
    End While
    
    ' Code should never reach here, but without this line you'll get a BC42105 warning:
    Return New SendEmailCompletedEventArgs(Nothing, True, Nothing, currentTry)
End Function

Public Async Function SendAllMessages() As Task
    Using smtpClient As SmtpClient = CreateSmtpClient()
        For Each item As SomeType In SomeListOfData
            Using message As MailMessage = CreateMessageFor(item)
                Dim result As SendEmailCompletedEventArgs = Await SendEmailAsync(smtpClient, message, RetryCount)
                ProcessSendResult(item, result)
            End Using
        Next
    End Using
End Function

for each job in jobs

   Await Compose

next

Function Compose()

   Build Message
   Attach PDF
   Build smtpClient
   Send
   Log send error

End Function

Function Send

   SendAsync

End Function

jkirkerx wrote:

It's OK to await again?

Await smtpClient.SendMailAsync(message).ConfigureAwait(False)

'This is the new sendEngine
Dim sE As New SendEngine()
sE.SendEmailAsync(smtpClient, mailMessage, 5)
AddHandler sE.SendEmailCompleted, _
Sub(sender As Object, e As SendEmailCompletedEventArgs)

  Console.WriteLine(e.Error)
  If (e.Error IsNot Nothing) Then

      model.Error_Text = e.Error.HResult
      model.Error_Text = e.Error.Message.ToString
      model.TimeStamp_Error = DateTime.Now()
      ef_model_smtp_resend.Write_Smtp_Send_Record(model)

  End If
End Sub

com1 = My.Computer.Ports.OpenSerialPort("COM1")
        com1.ReadTimeout = 10000
        Do
            Dim Incoming As String = com1.ReadLine()
            If Incoming Is Nothing Then
                Exit Do
            Else
                returnStr &= Incoming & vbCrLf
            End If

Public Class Form1

    Dim myport As Array
    Dim strWeight As String

    Public Delegate Sub myDel(ByVal txtBox As TextBox)
    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load

        myport = SerialPort.GetPortNames

        AddHandler SerialPort1.DataReceived, AddressOf SerialPort1_DataReceived
    End Sub

    Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived

        txtBox.Invoke(New myDel(AddressOf UpdateTextBox), New Object() {txtBox})
    End Sub

    Public Sub UpdateTextBox(ByVal UpDateTextBox As TextBox)

        Dim bytes As Integer = SerialPort1.BytesToRead
        Dim Buffer(bytes) As Byte

        SerialPort1.Read(Buffer, 0, bytes)

        strWeight = System.Text.Encoding.Default.GetString(Buffer)
        txtBox.AppendText(strWeight)
        GetTareandWeight(strWeight)

    End Sub

    Private Sub GetTareandWeight(ByVal weight As String)

        Dim strWeights() As String
        Dim newWeight As String = Replace(weight, " ", " ")
        strWeights = Split(weight, ",")

        txtBox2.Text &= newWeight & vbCrLf
        txtBox2.Text &= strWeights.Length.ToString & vbCrLf
        txtBox2.Text &= "Tare: " & strWeights(1).ToString
    End Sub

    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click

        SerialPort1.PortName = "COM5"
        SerialPort1.BaudRate = 9600
        SerialPort1.DataBits = 8
        SerialPort1.Parity = Parity.None
        SerialPort1.StopBits = StopBits.One
        SerialPort1.Handshake = Handshake.None
        SerialPort1.Open()

        SerialPort1.Write(vbCr)

    End Sub

Public Sub AddCustomHeader(ByVal mail As MailItem, ByVal headerName As String, ByVal headerValue As String)
    Dim prop As String = "http://schemas.microsoft.com/mapi/string/{00020386-0000-0000-C000-000000000046}/" + headerName
    mail.PropertyAccessor.SetProperty(prop, headerValue)
End Sub

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