Preface
A good principle of program development is to separate usage from creation. How many people adopted this style five years ago? Hardly any. Nowadays, IOC is popular or even rampant. Some teams do not use IOC containers. Some are due to historical reasons, and some are due to team culture. Instead of using the IOC team, find an opportunity to embrace it.
I've been using IOC containers. Here's how to integrate IOC into WebForm and WebMvc applications.
Automatic injection to ASPX and ASHX
Framework support
1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6
7 namespace Happy.Web
8 {
9 public interface IWantAutoDependInjection
10 {
11 }
12 } 1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6
7 namespace Happy.Web
8 {
9 [AttributeUsage(AttributeTargets.Property, AllowMultiple = false)]
10 public sealed class DependToAttribute : Attribute
11 {
12 public Type DependToType { get; set; }
13
14 public string Key { get; set; }
15 }
16 } 1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6
7 using System.Web;
8
9 using Microsoft.Practices.ServiceLocation;
10
11 using Happy.ExtensionMethods.Reflection;
12
13 namespace Happy.Web
14 {
15 public class DependInjectionModule : IHttpModule
16 {
17 public void Init(HttpApplication context)
18 {
19 context.PreRequestHandlerExecute += OnPreRequestHandlerExecute;
20 }
21
22 private void OnPreRequestHandlerExecute(object sender, EventArgs e)
23 {
24 if (!(HttpContext.Current.CurrentHandler is IWantAutoDependInjection))
25 {
26 return;
27 }
28
29 var properties = HttpContext.Current.CurrentHandler.GetType().GetProperties();
30
31 foreach (var property in properties)
32 {
33 var dependToAttribute = property.GetAttribute<DependToAttribute>(false);
34
35 if (dependToAttribute == null)
36 {
37 continue;
38 }
39
40 var dependType = dependToAttribute.DependToType ?? property.PropertyType;
41
42 var value = ServiceLocator.Current.GetInstance(dependType, dependToAttribute.Key ?? string.Empty);
43
44 property.SetValue(HttpContext.Current.Handler, value);
45 }
46 }
47
48 public void Dispose()
49 {
50 }
51 }
52 }Code example
1 <configuration>
2 <system.web>
3 <compilation debug="true" targetFramework="4.5" />
4 <httpRuntime targetFramework="4.5" />
5 </system.web>
6
7 <system.webServer>
8 <modules>
9 <add name="DependInjectionModule" type="Happy.Web.DependInjectionModule"/>
10 </modules>
11 </system.webServer>
12
13 </configuration> 1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Web;
5 using System.Web.UI;
6 using System.Web.UI.WebControls;
7
8 using Happy.Web;
9
10 namespace WebStudy
11 {
12 public partial class Test : System.Web.UI.Page, IWantAutoDependInjection
13 {
14 [DependTo]
15 public ApplicationService ApplicationService { get; set; }
16
17 protected void Page_Load(object sender, EventArgs e)
18 {
19 this.Response.Write(this.ApplicationService.GetMessage());
20 }
21 }
22
23 public sealed class ApplicationService
24 {
25 public string GetMessage()
26 {
27 return "Guang Wei Du";
28 }
29 }
30 }Operation result
Automatic injection to MVC
Framework support (latest version)
1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6
7 using System.Web.Routing;
8 using System.Web.Mvc;
9
10 using Microsoft.Practices.ServiceLocation;
11
12 using Happy.DesignByContract;
13
14 namespace Happy.Web.Mvc
15 {
16 public sealed class ServiceLocationDependencyResolver : IDependencyResolver
17 {
18 private readonly IServiceLocator _serviceLocator;
19
20 public ServiceLocationDependencyResolver(IServiceLocator serviceLocator)
21 {
22 Check.RequireNotNull(serviceLocator, "serviceLocator");
23
24 _serviceLocator = serviceLocator;
25 }
26
27 public object GetService(Type serviceType)
28 {
29 Check.RequireNotNull(serviceType, "serviceType");
30
31 try
32 {
33 return _serviceLocator.GetInstance(serviceType);
34 }
35 catch
36 {
37 return null;
38 }
39 }
40
41 public IEnumerable<object> GetServices(Type serviceType)
42 {
43 Check.RequireNotNull(serviceType, "serviceType");
44
45 try
46 {
47 return _serviceLocator.GetAllInstances(serviceType);
48 }
49 catch
50 {
51 return new List<object>();
52 }
53 }
54 }
55 }Code example
Code examples are omitted here. If you are interested, please leave a message.
Remarks
Imagine how refreshing it would be for developers to define and declare without needing to assemble by hand. IOC containers are best configured automatically according to the convention.