MessageBox.Show("发送失败!","提示", MessageBoxButtons.OK, MessageBoxIcon.Warning)

mark 处理异步发送邮件

全局代码处理

Public Sub SendCompletedCallback(ByVal sender As Object, ByVal e As System.ComponentModel.AsyncCompletedEventArgs)
\' Get the unique identifier for this asynchronous operation.
Dim token As String = CStr(e.UserState)

If e.Cancelled Then
    output.show("[" & token & "] Send canceled.")
End If
If e.Error IsNot Nothing Then
    output.show("[{" & token & "}] {" & e.Error.ToString() & "}" )
Else
    output.show("Message sent.")
End If

End Sub

发送代码

Dim client As New Net.Mail.SmtpClient("smtp.126.com")
\'client.Timeout = 60000

client.UseDefaultCredentials = True
client.Credentials = new System.Net.NetworkCredential("lin_hailun@126.com", "6849338.")
client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network

Dim [from] As New Net.Mail.MailAddress("lin_hailun@126.com", "lin " & ChrW(&HD8) & " hailun", System.Text.Encoding.UTF8)
\' Set destinations for the e-mail message.
Dim [To] As New Net.Mail.MailAddress("2450314695@qq.com")
\' Specify the message content.
Dim message As New Net.Mail.MailMessage([from], [To])

message.Body = "This is a test e-mail message sent by an application. "
\' Include some non-ASCII characters in body and subject.
Dim someArrows As New String(New Char() {ChrW(&H2190), ChrW(&H2191), ChrW(&H2192), ChrW(&H2193)})
message.Body += Environment.NewLine & someArrows
message.BodyEncoding = System.Text.Encoding.UTF8
message.Subject = "test message 1" & someArrows
message.SubjectEncoding = System.Text.Encoding.UTF8
\' Set the method that is called back when the send operation ends.
AddHandler client.SendCompleted, AddressOf SendCompletedCallback

Dim userState As String = "test message1"
client.SendAsync(message, userState)

同步发送

Dim client As New System.Net.Mail.SmtpClient("smtp.qq.com", 587) \'或者465
client.EnableSsl = True \'SSL

client.Credentials = New System.Net.NetworkCredential("455189993@qq.com", "helen6849338.")
client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network
Dim message As New System.Net.Mail.MailMessage()

message.From = new System.Net.Mail.MailAddress("455189993@qq.com","别名")

\'message.To.Add(new System.Net.Mail.MailAddress("2450314695@qq.com","人名"))
message.To.Add("2450314695@qq.com")
message.Subject = "邮件测试"
message.BodyEncoding = System.Text.Encoding.UTF8

Dim content As String

content &= "这是文字" & vbcrlf
content &= "也是文字"

message.Body = content

Try
    client.Send(message)
    msgbox("发送成功")
Catch ex As Exception
    msgbox("发送失败:" & ex.message)
End Try

异步发送

Dim client As New System.Net.Mail.SmtpClient("smtp.qq.com", 587) \'或者465
client.EnableSsl = True \'SSL

client.Credentials = New System.Net.NetworkCredential("455189993@qq.com", "helen6849338.")
client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network
Dim message As New System.Net.Mail.MailMessage()

message.From = new System.Net.Mail.MailAddress("455189993@qq.com","别名")

\'message.To.Add(new System.Net.Mail.MailAddress("2450314695@qq.com","人名"))
message.To.Add("2450314695@qq.com")
message.Subject = "邮件测试"
message.BodyEncoding = System.Text.Encoding.UTF8

Dim content As String

content &= "这是文字" & vbcrlf
content &= "也是文字"

message.Body = content

AddHandler client.SendCompleted, AddressOf SendCompletedCallback

Dim userState As String = "test message1"
client.SendAsync(message, userState)