Unity 2 – Configuration file and Unity (Part 2)

I’m real fan of Unity, I already worked with other Ioc, but Unity remains my favorite.

In my previous post, I explained how to configure Unity at runtime. This one will describe how to use the configuration file.

First of all add the following references to your project:

• System.Configuration.dll
• Microsoft.Practices.Unity.Configuration.dll

Simple scenario

Add a using directive to get easy access to the container initializer:

Code Snippet

1. using Microsoft.Practices.Unity.Configuration;

Update the Program class as follows:

Code Snippet

1. class Program
2. {
3.     static void Main(string[] args)
4.     {
5.         IUnityContainer container;
6.         container = new UnityContainer();
7.  
8.         // Initialize the container with the config file
9.         container.LoadConfiguration();
10.         // Resolve IMyComponent
11.         IMyComponent obj = container.Resolve<IMyComponent>();
12.  
13.         Console.WriteLine(obj.Run(5));
14.  
15.         Console.ReadKey();
16.     }
17. }

Add a configuration file (which is a simple XML file):

Code Snippet

1. <?xml version="1.0" encoding="utf-8" ?>
2. <configuration>
3.     <configSections>
4.         <section name="unity" type="Microsoft.Practices.Unity.Configuration.UnityConfigurationSection, Microsoft.Practices.Unity.Configuration"/>
5.     </configSections>
6.     <unity xmlns="https://schemas.microsoft.com/practices/2010/unity">
7.         <container>
8.             <register type="UnityTest.IMyComponent, UnityTest" mapTo="UnityTest.MyComponent, UnityTest"  />
9.         </container>
10.     </unity>
11.  
12. </configuration>

Run the example and the result is the same as in my previous post.

Singleton scenario

To use the injected object as a singleton, just define a ControledContainerLifetimeManager, which manages the lifetime of your object as a unique instance:

Code Snippet

1. <?xml version="1.0" encoding="utf-8" ?>
2. <configuration>
3.     <configSections>
4.         <section name="unity" type="Microsoft.Practices.Unity.Configuration.UnityConfigurationSection, Microsoft.Practices.Unity.Configuration"/>
5.     </configSections>
6.     <unity xmlns="https://schemas.microsoft.com/practices/2010/unity">
7.         <container>
8.             <register type="UnityTest.IMyComponent, UnityTest" mapTo="UnityTest.MyComponent, UnityTest"  >
9.                 <lifetime type="Microsoft.Practices.Unity.ContainerControlledLifetimeManager, Microsoft.Practices.Unity" />
10.             </register>
11.         </container>
12.     </unity>
13.  
14. </configuration>

Alias scenario

For the alias scenario, remove the previous configuration file, and change the code as follows :

Code Snippet

1. class Program
2. {
3.     static void Main(string[] args)
4.     {
5.         IUnityContainer container;
6.         const string FRENCH = "fr";
7.         const string DEFAULT = "us";
8.         // Use the runtime configuration
9.         container = new UnityContainer();
10.  
11.         // Initialize the container with the config file
12.         container.LoadConfiguration();
13.  
14.         // Resolve IMyComponent
15.         IMyComponent obj = container.Resolve<IMyComponent>(DEFAULT);
16.         IMyComponent objFr = container.Resolve<IMyComponent>(FRENCH);
17.  
18.         Console.WriteLine(obj.Run(5));
19.         Console.WriteLine(objFr.Run(5));
20.  
21.         Console.ReadKey();
22.     }
23. }

Then use the following configuration file instead, which defines the aliases with the name attribute:

Code Snippet

1. <?xml version="1.0" encoding="utf-8" ?>
2. <configuration>
3.     <configSections>
4.         <section name="unity" type="Microsoft.Practices.Unity.Configuration.UnityConfigurationSection, Microsoft.Practices.Unity.Configuration"/>
5.     </configSections>
6.     <unity xmlns="https://schemas.microsoft.com/practices/2010/unity">
7.         <container>
8.             <register type="UnityTest.IMyComponent, UnityTest" mapTo="UnityTest.MyComponent, UnityTest" name="us" >
9.                 <lifetime type="Microsoft.Practices.Unity.ContainerControlledLifetimeManager, Microsoft.Practices.Unity" />
10.             </register>
11.             <register type="UnityTest.IMyComponent, UnityTest" mapTo="UnityTest.MyComponentFr, UnityTest" name="fr" >
12.                 <lifetime type="Microsoft.Practices.Unity.ContainerControlledLifetimeManager, Microsoft.Practices.Unity" />
13.             </register>
14.         </container>
15.     </unity>
16.  
17. </configuration>

Comments

• Anonymous
  September 12, 2011
  Thanks for this, I was having problems finding a clear example.
• Anonymous
  November 14, 2012
  I am getting this error somehow. Binding file and references look ok.System.Configuration.ConfigurationErrorsException: Configuration system failed to initialize ---> System.Configuration.ConfigurationErrorsException: Unrecognized configuration section unity.Any idea on this?