在asp.net web form中实现autofac

Question

I am developing ASP.net Web Form, and I want to implement AutoFac into the website.

I have followed the steps in following link: https://autofaccn.readthedocs.io/en/latest/integration/webforms.html

But I got this error:

This module requires that the HttpApplication (Global Application Class) implements IContainerProviderAccessor.

I can't find Global.asax.cs in my project, only Global.asax .

Global.asax :

<%@ Application Language="C#" %>
<%@ Import Namespace="Autofac" %>
<%@ Import Namespace="Autofac.Integration.Web" %>
<script RunAt="server">
    public class Global : HttpApplication, IContainerProviderAccessor {

        // Provider that holds the application container.
        static IContainerProvider _containerProvider;

        // Instance property that will be used by Autofac HttpModules
        // to resolve and inject dependencies.
        public IContainerProvider ContainerProvider {
            get { return _containerProvider; }
        }

        void Application_Start(object sender, EventArgs e) {
            // Code that runs on application startup

            // Build up your application container and register your dependencies.
            var builder = new ContainerBuilder();
            //builder.RegisterType<SomeDependency>();
            // ... continue registering dependencies...

            // Once you're done registering things, set the container
            // provider up with your registrations.
            _containerProvider = new ContainerProvider(builder.Build());
        }
    }
</script>

Any ideas? Thank you very much!

Answer 1

I had this problem too and fixed it by creating a global.asax.cs file and referencing this from the original global.asax file. This enables you to implement the required IContainerProviderAccessor interface.

File: Global.asax

<%@ Application Codebehind="Global.asax.cs" Inherits="MyCompany.WebForms.Global" Language="C#" %>

File: Global.asax.cs

using Autofac;
using Autofac.Core;
using Autofac.Integration.Web;
using ....


namespace MyCompany.WebForms
{ 
    public partial class Global : HttpApplication, IContainerProviderAccessor
    {
        // Provider that holds the application container.
        static IContainerProvider _containerProvider;

        // Instance property that will be used by Autofac HttpModules
        // to resolve and inject dependencies.
        public IContainerProvider ContainerProvider
        {
            get { return _containerProvider; }
        }

        protected void Application_Start(object sender, EventArgs e)
        {
             ....
        }
    }
}

After implementing this, I also had problems with Could not load type 'MyCompany.WebForms.Global' errors until I moved Global.asax.cs file into the App_Code folder and updated the CodeBehind reference Global.asax .

Answer 2

<configuration>
  <system.web>
<httpModules>
  <!-- This section is used for IIS6 -->
  <add
    name="ContainerDisposal"
    type="Autofac.Integration.Web.ContainerDisposalModule, Autofac.Integration.Web"/>
  <add
    name="PropertyInjection"
    type="Autofac.Integration.Web.Forms.PropertyInjectionModule, Autofac.Integration.Web"/>
</httpModules>
</system.web>
    <system.webServer>
    <!-- This section is used for IIS7 -->
<modules>
  <add
    name="ContainerDisposal"
    type="Autofac.Integration.Web.ContainerDisposalModule, Autofac.Integration.Web"
    preCondition="managedHandler"/>
  <add
    name="PropertyInjection"
    type="Autofac.Integration.Web.Forms.PropertyInjectionModule, Autofac.Integration.Web"
    preCondition="managedHandler"/>
</modules>
</system.webServer>
</configuration>

These sections must be defined in the web.config file in order for injection to work. See https://code.google.com/p/autofac/wiki/WebFormsIntegration#Implement_IContainerProviderAccessor_in_Global.asax