在VB.net上發送電子郵件

Question

誰能幫我。 我創建了一個電子郵件程序。 單擊發送按鈕時出現錯誤。 這是我的代碼：

Imports System.Net.Mail

Public Class frmEmail
Dim emailaddress As String
Dim password As String
Dim port As Integer
Dim host As String

Private Sub frmEmail_Load(sender As Object, e As EventArgs)

 If emailaddress.ToLower.Contains("@gmail") Then
        port = 587
        host = "smtp.gmail.com"
    ElseIf emailaddress.ToLower.Contains("@yahoo") Then
        port = 465
        host = "smtp.mail.yahoo.com"
    End If

End Sub

Private Sub btnSend_Click(ByVal sender As Object, ByVal e As    EventArgs) Handles btnSend.Click
    Try
        Dim smtpServer As New SmtpClient
        Dim mail As New MailMessage()
        smtpServer.Credentials = New Net.NetworkCredential(emailaddress, password)
        smtpServer.Port = port
        smtpServer.Host = host
        smtpServer.EnableSsl = True
        mail = New MailMessage()
        mail.From = New MailAddress(emailaddress)
        mail.To.Add(txtTo.Text)
        mail.Subject = txtSubject.Text
        mail.Body = txtMessage.Text
        smtpServer.Send(mail)
        MsgBox("The mail is send!", MsgBoxStyle.Information)
    Catch error_t As Exception
        MsgBox(error_t.ToString)
    End Try
End Sub
End Class

而且我遇到了以下錯誤：System.ArgumentOutOfRangeException：指定的參數不在有效值范圍內。 參數名稱：System.Net.Mail.SmtpClient.set_Port處的值（Int32值）

***編輯忘記將其修改為原始代碼

Answer 1

您的子私人子frmEmail_Load（作為對象發送，作為EventArgs發送）

窗體加載時不運行。

由於此port設置為默認值0

您需要告訴VB.Net在表單加載時運行，如下所示

Private Sub frmEmail_Load(sender As Object, e As EventArgs) Handles MyBase.Load

同樣在代碼下方，您可能會發現從電子郵件服務器收到有關身份驗證的錯誤。 如果得到這個，就在下面

Dim smtpServer As New SmtpClient

加上這個

smtpServer.UseDefaultCredentials = False

它可能會起作用。