我需要从异步操作发送异步电子邮件。我不明白为什么会发生以下错误，因为我在其他项目中使用了相同的类并且仅使用相同的形式而没有错误，一切都很安静。

错误:

The asynchronous action method 'EsqueciMinhaSenhaAsync' returns a Task, which cannot be executed synchronously.

行动:

        [AllowAnonymous]
        [HttpPost, ValidateAntiForgeryToken]
        public async Task<ActionResult> EsqueciMinhaSenhaAsync(UsuarioEsqueciMinhaSenhaViewModel vModel)
        {
            if (ModelState.IsValid)
            {
                var conteudo = "este é o conteudo do email";
                var nomeRemetente = "esse é o nome do remetente";

                if(await EmailService.SendAsync(Language.PasswordRecovery, conteudo, vModel.EmailOuUsername, nomeRemetente))
                {
                    TempData["MensagemRetorno"] = Language.EmailSendedWithSuccess;
                    return View("login");
                }
            }

            TempData["MensagemRetorno"] = Language.ErrorSendingEmail;
            return View("EsqueciMinhaSenha");
        }

我的电子邮件服务:

    public static async Task<bool> SendAsync(string assunto, string conteudo, string destinatario, string nomeDestinatario)
    {
        // Habilitar o envio de e-mail
        var appSetting = ConfigurationManager.AppSettings;

        if (appSetting != null && appSetting.Count >= 7 && !string.IsNullOrEmpty(assunto) && !string.IsNullOrEmpty(conteudo) && !string.IsNullOrEmpty(destinatario) && !string.IsNullOrEmpty(nomeDestinatario))
        {
            int port = 0;
            bool useSSl = false;

            using (var msg = new MailMessage
            {
                From = new MailAddress(appSetting["EmailFrom"], appSetting["EmailNameFrom"]),
                Body = WebUtility.HtmlEncode(conteudo)
            })
            {
                int.TryParse(appSetting["EmailPort"], out port);
                bool.TryParse(appSetting["EmailUseSSL"], out useSSl);


                msg.ReplyToList.Add(destinatario);
                msg.To.Add(new MailAddress(destinatario, nomeDestinatario));
                msg.Subject = assunto;
                msg.AlternateViews.Add(AlternateView.CreateAlternateViewFromString(msg.Body, null, MediaTypeNames.Text.Plain));
                msg.AlternateViews.Add(AlternateView.CreateAlternateViewFromString(msg.Body, null, MediaTypeNames.Text.Html));

                using (var smtpClient = new SmtpClient(appSetting["EmailServer"], port))
                {
                    var credentials = new NetworkCredential(appSetting["EmailUserName"], appSetting["EmailPassword"]);
                    smtpClient.Credentials = credentials;
                    smtpClient.EnableSsl = useSSl;
                    await smtpClient.SendMailAsync(msg);

                    return await Task.FromResult(true);
                }
            }
        }

        return await Task.FromResult(false);
    }

堆栈跟踪:

[InvalidOperationException: The asynchronous action method 'esqueciminhasenha' returns a Task, which cannot be executed synchronously.]
System.Web.Mvc.Async.TaskAsyncActionDescriptor.Execute(ControllerContext controllerContext, IDictionary2 parameters) +119<br/> System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary2 parameters) +27
System.Web.Mvc.<>c__DisplayClass15.b__12() +55 System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func1 continuation) +253<br/> System.Web.Mvc.<>c__DisplayClass17.<InvokeActionMethodWithFilters>b__14() +22 System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList1 filters, ActionDescriptor actionDescriptor, IDictionary2 parameters) +189<br/> System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +521<br/> System.Web.Mvc.Controller.ExecuteCore() +95<br/> MusiArtist.MVC.Areas.admin.Controllers.BaseController.ExecuteCore() in F:\Backup\BitBucket\negrini.musiartist\src\MusiArtist.MVC\Areas\admin\Controllers\BaseController.cs:29 System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +180 System.Web.Mvc.<>c__DisplayClass19.<BeginExecute>b__13() +18 System.Web.Mvc.Async.AsyncResultWrapper.<.cctor>b__0(IAsyncResult asyncResult, Action action) +15<br/> System.Web.Mvc.Async.WrappedAsyncResult2.CallEndDelegate(IAsyncResult asyncResult) +16
System.Web.Mvc.Async.WrappedAsyncResultBase1.End() +49<br/> System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +26<br/> System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +10<br/> System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState) +21<br/> System.Web.Mvc.Async.WrappedAsyncVoid1.CallEndDelegate(IAsyncResult asyncResult) +29
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +28 System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9765121 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

最佳答案

我重写了 Controller 的“DisableAsyncSupport”方法并将 getter 设置为 false，一切正常!!!

protected override bool DisableAsyncSupport
{
    get { return false; }
}

我相信通过继承自 Controller (我有自己的 Controller “ControllerBase”)，该方法的行为必须有所不同。

关于c# - 具有异步操作的 ASP.NET MVC，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/41669047/