Reputation: 507
I'm using Unity2.0, and try to resolve a open generic type. The classes are defined as follow:
public interface IRepository<T>
{
void Add(T t);
void Delete(T t);
void Save();
}
public class SQLRepository<T> : IRepository<T>
{
#region IRepository<T> Members
public void Add(T t)
{
Console.WriteLine("SQLRepository.Add()");
}
public void Delete(T t)
{
Console.WriteLine("SQLRepository.Delete()");
}
public void Save()
{
Console.WriteLine("SQLRepository.Save()");
}
#endregion
}
The config file is like:
<unity xmlns="http://schemas.microsoft.com/practices/2010/unity">
<namespace name="UnityTry"/>
<assembly name="UnityTry"/>
<container>
<register type="IRepository[]" mapTo="SQLRepository[]" name="SQLRepo" />
</container>
</unity>
the code to resolve IRepository:
IUnityContainer container = new UnityContainer();
UnityConfigurationSection section = (UnityConfigurationSection)ConfigurationManager.GetSection("unity");
section.Containers.Default.Configure(container);
IRepository<string> rep = container.Resolve<IRepository<string>>();
rep.Add("World");
When I run the code, ResolutionFailedException will be raised at line:
IRepository<string> rep = container.Resolve<IRepository<string>>();
The exception message is :
Exception is: InvalidOperationException - The current type, UnityTry.IRepository`1 [System.String], is an interface and cannot be constructed. Are you missing a type mapping?
Anyone has any ideas of what I have done wrong?
Upvotes: 1
Views: 3757
Reputation: 22655
The open generic is registered with a mapping using the name "SQLRepo" but when resolved a name is not supplied so Unity cannot find the mapping. Try resolving by name:
IRepository<string> rep = container.Resolve<IRepository<string>>("SQLRepo");
Upvotes: 1