我意识到这是一个非常古老的问题的答案，还有很多其他好的答案。我发布此代码以包含其他用户发布的一些有用的 cmets，例如 Using Statements 和一些答案已经过时的新方法。自 2018 年 7 月 11 日起，此代码已经过测试并可以正常运行。
如果通过您的 GMail 帐户发送，请确保从您的 control panel 启用 Allow less secure apps
类代码 C#：
public class Email
{
public void NewHeadlessEmail(string fromEmail, string password, string toAddress, string subject, string body)
{
using (System.Net.Mail.MailMessage myMail = new System.Net.Mail.MailMessage())
{
myMail.From = new MailAddress(fromEmail);
myMail.To.Add(toAddress);
myMail.Subject = subject;
myMail.IsBodyHtml = true;
myMail.Body = body;
using (System.Net.Mail.SmtpClient s = new System.Net.Mail.SmtpClient("smtp.gmail.com", 587))
{
s.DeliveryMethod = SmtpDeliveryMethod.Network;
s.UseDefaultCredentials = false;
s.Credentials = new System.Net.NetworkCredential(myMail.From.ToString(), password);
s.EnableSsl = true;
s.Send(myMail);
}
}
}
}
类代码 VB：
Public Class Email
Sub NewHeadlessEmail(fromEmail As String, password As String, toAddress As String, subject As String, body As String)
Using myMail As System.Net.Mail.MailMessage = New System.Net.Mail.MailMessage()
myMail.From = New MailAddress(fromEmail)
myMail.To.Add(toAddress)
myMail.Subject = subject
myMail.IsBodyHtml = True
myMail.Body = body
Using s As New Net.Mail.SmtpClient("smtp.gmail.com", 587)
s.DeliveryMethod = SmtpDeliveryMethod.Network
s.UseDefaultCredentials = False
s.Credentials = New Net.NetworkCredential(myMail.From.ToString(), password)
s.EnableSsl = True
s.Send(myMail)
End Using
End Using
End Sub
End Class
使用 C#：
{
Email em = new Email();
em.NewHeadlessEmail("myemail@gmail.com", "password", "recipient@email.com", "Subject Text", "Body Text");
}
使用 VB：
Dim em As New Email
em.NewHeadlessEmail("myemail@gmail.com", "password", "recipient@email.com", "Subject Text", "Body Text")