等待mvc4不起作用

Question

I have a problem with my code, await key word does not work in asp.net mvc4, I do not know what is the problem but when I wrote it the .net framework did not color it by blue!!

this is my code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Security;
using workflow.Authorize;
using System.Web.Script.Serialization;
using workflow.DataHolders;
using workflow.Models;
using workflow;
using System.Net;
using System.Net.Mail;

    [AllowAnonymous]
    [HttpPost]
    [ValidateAntiForgeryToken]
    public ActionResult ValidateAndSignUp(ForCompany newCompany)
    {
        if (ModelState.IsValid)
        {
            company NewCompany = new company();
            TryUpdateModel(NewCompany);
            context.companies.Add(NewCompany);
            int processStatus= context.SaveChanges();
            if (processStatus != 0)
            {
                MailMessage message = new MailMessage();
                message.To.Add(newCompany.Email);
                message.Subject = "You have created new account";
                message.Body = "Hi, Welcom to HWorkflow website this email is to approve your account and to creat the first user, please click on the link below to approve your account and to creat your first user";
                message.From = new MailAddress("HWorkflowTeam@hworkflow.com");
                message.IsBodyHtml = true;

                var credential = new NetworkCredential
                {
                    UserName = "hworkflowteam",  // replace with valid value
                    Password = "No-access"  // replace with valid value
                };
                var smtp = new SmtpClient();
                smtp.Credentials = credential;
                smtp.Host = "mail.hworkflow.com";
                smtp.Port = 25;
                smtp.EnableSsl = true;
                await smtp.SendMailAsync(message);

            }
            return RedirectToAction("index", "Home");
        }
        else
        {
            return View("signUp", newCompany);
        }
    }

so please could anyone help me to solve this problem.

Answer 1

You need to mark your method as async and to return a Task<T>

public async Task<ActionResult> ValidateAndSignUp(ForCompany newCompany)
{
    await ...
}    

Answer 2

Your Method Signature does not indicate that this is an async / awaitable method.

try

public async Task<ActionResult> ValidateAndSignUp(ForCompany newCompany)
....