邮件发送，但从不返回
问题描述：
我一直在一个网站，您可以直接发送查询邮件到特定的电子邮件。邮件发送，但从不返回
起初我以为邮件没有发送，因为我点击发送按钮后，网站只是继续加载。但是当我查看我的电子邮件时，我惊讶于我发送的邮件在那里。但是当我查看我的网站时（我有查询表单），它仍然在加载。
该ViewBag，假设说“您的消息已发送！”即使我已经收到邮件，仍然不显示。好像
await smtp.SendMailAsync(message);
不返回。我是新来的这种事情。我希望有人能帮助我。先谢谢你。这里是我的控制器：
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<ActionResult> Index(EmailFormModel model, IEnumerable<HttpPostedFileBase> files)
{
try
{
if (ModelState.IsValid)
{
List<string> paths = new List<string>();
foreach (var file in files)
{
if (file.ContentLength > 0)
{
var fileName = Path.GetFileName(file.FileName);
var path = Path.Combine(System.Web.HttpContext.Current.Server.MapPath("~/App_Data/uploads"), fileName);
file.SaveAs(path);
paths.Add(path);
}
}
var message = new MailMessage();
foreach (var path in paths)
{
var fileInfo = new FileInfo(path);
var memoryStream = new MemoryStream();
using (var stream = fileInfo.OpenRead())
{
stream.CopyTo(memoryStream);
}
memoryStream.Position = 0;
string fileName = fileInfo.Name;
message.Attachments.Add(new Attachment(memoryStream, fileName));
}
//Rest of business logic here
string EncodedResponse = Request.Form["g-Recaptcha-Response"];
bool IsCaptchaValid = (ReCaptcha.Validate(EncodedResponse) == "True" ? true : false);
if (IsCaptchaValid)
{
var body = "<p><b>Email From:</b> {0} ({1})</p><p><b>Subject:</b> {2} </p><p><b>Software Description:</b></p><p>{4}</p><p><b>Message:</b></p><p>{3}</p>";
message.To.Add(new MailAddress("[email protected]")); // replace with valid value
message.From = new MailAddress("[email protected]"); // replace with valid value
message.Subject = "(Inquire for SELLING)";
message.Body = string.Format(body, model.FromName, model.FromEmail, model.FromSubject, model.Message, model.Desc);
message.IsBodyHtml = true;
using (var smtp = new SmtpClient())
{
var credential = new NetworkCredential
{
UserName = "[email protected]", // replace with valid value
Password = "0000" // replace with valid value
};
smtp.Credentials = credential;
smtp.Host = "relay-hosting.secureserver.net";
smtp.Port = 25;
smtp.Timeout = 1000;
smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
smtp.UseDefaultCredentials = false;
smtp.SendCompleted += (s, e) =>
{
//delete attached files
foreach (var path in paths)
System.IO.File.Delete(path);
};
await smtp.SendMailAsync(message);
ViewBag.Message = "Your message has been sent!";
ModelState.Clear();
return View("Index");
}
}
else
{
TempData["recaptcha"] = "Please verify that you are not a robot!";
}
} return View(model);
}
catch (Exception ex)
{
return View("Error");
}
}
答
我以前遇到过这个问题。 Attachments正被保留并需要处理，然后才能删除它们。没有对.Dispose的调用，文件被锁定。试试这个：
[
HttpPost,
ValidateAntiForgeryToken
]
public async Task<ActionResult> Index(EmailFormModel model,
IEnumerable<HttpPostedFileBase> files)
{
try
{
if (ModelState.IsValid)
{
string EncodedResponse = Request.Form["g-Recaptcha-Response"];
bool IsCaptchaValid = ReCaptcha.Validate(EncodedResponse) == "True";
if (IsCaptchaValid)
{
var paths = GetUploadPaths(files);
using (var message = ConstructMailMessage(model))
{
AppendAttachments(paths, message.Attachments);
using (var smtp = new SmtpClient())
{
var credential = new NetworkCredential
{
UserName = "...", // replace with valid value
Password = "..." // replace with valid value
};
smtp.Credentials = credential;
smtp.Host = "relay-hosting.secureserver.net";
smtp.Port = 25;
smtp.Timeout = 1000;
smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
smtp.UseDefaultCredentials = false;
smtp.SendCompleted += (s, e) =>
{
// Ensure disposed first.
foreach (var a in message.Attachments) a.Dispose();
foreach (var path in paths) File.Delete(path);
};
await smtp.SendMailAsync(message);
ViewBag.Message = "Your message has been sent!";
ModelState.Clear();
return View("Index");
}
}
}
else
{
TempData["recaptcha"] = "Please verify that you are not a robot!";
}
}
return View(model);
}
catch (Exception ex)
{
return View("Error");
}
}
我试着在分离一些核心逻辑方面略有不同的方法。例如，现在有一个帮助器方法用于获取上传文件路径GetUploadPaths，另一个用于通过AppendAttachments将附件添加到.Attachments实例。此外，现在有一个ConstructMailMessage函数，它也可以。
public List<string> GetUploadPaths(IEnumerable<HttpPostedFileBase> files)
{
var paths = new List<string>();
foreach (var file in files)
{
if (file.ContentLength > 0)
{
var fileName = Path.GetFileName(file.FileName);
var path = Path.Combine(HttpContext.Current.Server.MapPath("~/App_Data/uploads"), fileName);
file.SaveAs(path);
paths.Add(path);
}
}
return paths;
}
public MailMessage ConstructMailMessage(EmailFormModel model)
{
var message = new MailMessage();
var body = "<p><b>Email From:</b> {0} ({1})</p><p><b>Subject:</b> {2} </p><p><b>Software Description:</b></p><p>{4}</p><p><b>Message:</b></p><p>{3}</p>";
message.To.Add(new MailAddress("[email protected]")); // replace with valid value
message.From = new MailAddress("[email protected]"); // replace with valid value
message.Subject = "(Inquire for SELLING)";
message.Body = string.Format(body, model.FromName, model.FromEmail, model.FromSubject, model.Message, model.Desc);
message.IsBodyHtml = true;
return message;
}
public void AppendAttachments(List<string> paths, AttachmentCollection attachments)
{
foreach (var path in paths)
{
var fileInfo = new FileInfo(path);
var memoryStream = new MemoryStream();
using (var stream = fileInfo.OpenRead())
{
stream.CopyTo(memoryStream);
}
memoryStream.Position = 0;
string fileName = fileInfo.Name;
attachments.Add(new Attachment(memoryStream, fileName));
}
}
什么是“smtp.SendMailAsync”的返回类型，由于您没有正确处理Synchronization上下文，所以程序由于死锁而挂起。你在用'Task'做什么，并检查SendMail函数中的阻塞点 –
如果你使用'Task.WaitAll'来返回'公共异步任务索引'，将其替换为'Task.WhenAll'或'await'，以避免阻塞同步上下文。最好是'await'，但那需要整个调用链才能'异步' –
首先尝试在没有附件的情况下重现此问题。 –