在申请结束前不会发送电子邮件

Question

我有一个使用SmtpClient发送电子邮件的应用程序,但在应用程序关闭之前不会发送电子邮件.我搜索并搜索以找到问题的解决方案,但我找不到.

系统确实安装了Symantec防病毒软件,这可能是问题所在.

有没有人能解决这个问题？

这是我正在使用的代码.

public class EMail
{
    private string server;
    public string Server {get{return this.server;}set{this.server = value;}}
    private string to;
    public string To {get{return this.to;}set{this.to = value;}}
    private string from;
    public string From {get{return this.from;}set{this.from = value;}}
    private string subject;
    public string Subject {get{return this.subject;}set{this.subject = value;}}
    private string body;
    public string Body {get{return this.body;}set{this.body = value;}}

    public EMail()
    {}
    public EMail(string _server, string _to, string _from, string _subject, string _body)
    {
        this.Server = _server;
        this.To = _to;
        this.From = _from;
        this.Subject = _subject;
        this.Body = _body;
    }   

    public void Send()
    {
        using(System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage(this.From, this.To, this.Subject, this.Body))
        {        
            message.IsBodyHtml = true;
            System.Net.Mail.SmtpClient client = new System.Net.Mail.SmtpClient(this.Server);
            client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;
            //I have tried this, but it still does not work.
            //client.ServicePoint.ConnectionLeaseTimeout = 0;
            try 
            {
                client.Send(message);
            }  
            catch(System.Exception ex) 
            {
                System.Windows.Forms.MessageBox.Show(ex.ToString());              
            }
        }
    }
}

编辑:

事实证明,电子邮件最终会在2-3分钟后发送.好像它正在被交换服务器排队,或者SmtpClient连接最终超时并被服务器关闭.

编辑:

我试过了.

client.ServicePoint.ConnectionLeaseTimeout = 1;
client.ServicePoint.MaxIdleTime = 1;

Answer 1

我终于; 在StackOverflow和其他各种研究资源的帮助下,找到了解决方案.通过设置System.Net.ServicePointManager.MaxServicePointIdleTime= 1,邮件立即发送.

这是最终的代码.

public class EMail
{
    private string server;
    public string Server {get{return this.server;}set{this.server = value;}}
    private string to;
    public string To {get{return this.to;}set{this.to = value;}}
    private string from;
    public string From {get{return this.from;}set{this.from = value;}}
    private string subject;
    public string Subject {get{return this.subject;}set{this.subject = value;}}
    private string body;
    public string Body {get{return this.body;}set{this.body = value;}}

    public EMail()
    {}
    public EMail(string _server, string _to, string _from, string _subject, string _body)
    {
        this.Server = _server;
        this.To = _to;
        this.From = _from;
        this.Subject = _subject;
        this.Body = _body;
    }   

    public void Send()
    {
        using(System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage(this.From, this.To, this.Subject, this.Body))
        {        
            message.IsBodyHtml = true;
            System.Net.Mail.SmtpClient client = new System.Net.Mail.SmtpClient(this.Server);
            client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;

            int temp = System.Net.ServicePointManager.MaxServicePointIdleTime; //<- Store the original value.
            System.Net.ServicePointManager.MaxServicePointIdleTime = 1; //<- Change the idle time to 1.

            try 
            {
                client.Send(message);
            }  
            catch(System.Exception ex) 
            {
                System.Windows.Forms.MessageBox.Show(ex.ToString());              
            }
            finally
            {
                System.Net.ServicePointManager.MaxServicePointIdleTime = temp; //<- Set the idle time back to what it was.
            }
        }
    }
}

感谢大家的帮助!特别是冰人.