如何注入到EmailMessageService

Question

我在注入服务时遇到问题。我有一个ISettingService。我正在我的应用程序上测试注册，并使用电子邮件确认。

因此，在继承自IIdentityMessageService 的EmailMessageService类

我用Unity做Ioc。我在unity配置中注册了ISettingService，如下

.RegisterType<ISettingService, SettingService>()

我需要将此接口注入EmailMessageService类以访问设置。

这是EmailMessageService类

public class EmailMessagingService : IIdentityMessageService
{
    private ISettingService SettingService { get; set; }
    public Task SendAsync(IdentityMessage message)
    {
        var fromEmailAddress = ConfigurationManager
            .AppSettings["IdentityFromEmailAddress"];
        var text = message.Body;
        var html = message.Body;
        // Do whatever you want to the message
        using (var msg = new MailMessage())
        {
            msg.From = new MailAddress(fromEmailAddress);
            msg.To.Add(new MailAddress(message.Destination));
            msg.Subject = message.Subject;
            msg.AlternateViews.Add(
                AlternateView.CreateAlternateViewFromString(
                    text, null, MediaTypeNames.Text.Plain)
                );
            msg.AlternateViews.Add(
                AlternateView.CreateAlternateViewFromString(
                    html, null, MediaTypeNames.Text.Html)
                );

            // var smtpClient = new SmtpClient("smtp.whatever.net", Convert.ToInt32(587));
            // var credentials = new System.Net.NetworkCredential(Keys.EmailUser, Keys.EMailKey);
            // smtpClient.Credentials = credentials;
            using (var smtpClient = new SmtpClient())
            {
                var setting = SettingService.Query().Select().FirstOrDefault();
                if (setting != null)
                {
                    if (!string.IsNullOrEmpty(setting.SmtpHost))
                    {
                        smtpClient.Host = setting.SmtpHost;
                        smtpClient.Port = Convert.ToInt32(setting.SmtpPort);
                        if (setting.IsSmtpSsl)
                        {
                            smtpClient.EnableSsl = true;
                        }
                    }
                }
                smtpClient.Send(msg);
            }
        }
        return Task.FromResult(0);
    }
}

EmailMessageService类在Startup.Auth 上实例化

            var manager =
            new ApplicationUserManager(
                new ApplicationUserStore(context.Get<DataContext>()));
            ...
            manager.EmailService = new EmailMessagingService();

我不能使用构造函数注入作为这个直接调用的原因。所以我使用了setter注入。但我得到了类似"对象引用未设置为对象实例"的错误

var setting = SettingService.Query().Select().FirstOrDefault();

在EmailMessageService中。

Answer 1

O.K我不知道发生了什么，但通过更改UnityMvcActivator Start方法，如下所示。

public static void Start()
    {
        var container = ContainerManager.GetConfiguredContainer();
        UnityConfig.RegisterTypes(container);
        FilterProviders.Providers.Remove(FilterProviders.Providers.OfType<FilterAttributeFilterProvider>().First());
        FilterProviders.Providers.Add(new UnityFilterAttributeFilterProvider(container));
        DependencyResolver.SetResolver(new UnityDependencyResolver(container));
        var assemblies = AppDomain.CurrentDomain.GetAssemblies();
        try
        {
            //http://stackoverflow.com/questions/699852/how-to-find-all-the-classes-which-implement-a-given-interface
            foreach (var assembly in assemblies)
            {
                var instances = from t in assembly.GetTypes()
                                where t.GetInterfaces().Contains(typeof(IDependencyRegister))
                                         && t.GetConstructor(Type.EmptyTypes) != null
                                select Activator.CreateInstance(t) as IDependencyRegister;
                foreach (var instance in instances.OrderBy(x => x.Order))
                {
                    instance.Register(container);
                }
            }
        }
        catch (ReflectionTypeLoadException ex)
        {
        http://stackoverflow.com/questions/1091853/error-message-unable-to-load-one-or-more-of-the-requested-types-retrieve-the-l
            System.Text.StringBuilder sb = new System.Text.StringBuilder();
            foreach (Exception exSub in ex.LoaderExceptions)
            {
                sb.AppendLine(exSub.Message);
                System.IO.FileNotFoundException exFileNotFound = exSub as System.IO.FileNotFoundException;
                if (exFileNotFound != null)
                {
                    if (!string.IsNullOrEmpty(exFileNotFound.FusionLog))
                    {
                        sb.AppendLine("Fusion Log:");
                        sb.AppendLine(exFileNotFound.FusionLog);
                    }
                }
                sb.AppendLine();
            }
            string errorMessage = sb.ToString();
            throw new Exception(errorMessage, ex);
            //Display or log the error based on your application.
        }

        // TODO: Uncomment if you want to use PerRequestLifetimeManager
        // Microsoft.Web.Infrastructure.DynamicModuleHelper.DynamicModuleUtility.RegisterModule(typeof(UnityPerRequestHttpModule));
    }