How to create a fully lazy singleton for generics
- by Brendan Vogt
I have the following code implementation of my generic singleton provider:
public sealed class Singleton<T> where T : class, new()
{
Singleton()
{
}
public static T Instance
{
get { return SingletonCreator.instance; }
}
class SingletonCreator
{
static SingletonCreator()
{
}
internal static readonly T instance = new T();
}
}
This sample was taken from 2 articles and I merged the code to get me what I wanted:
http://www.yoda.arachsys.com/csharp/singleton.html and
http://www.codeproject.com/Articles/11111/Generic-Singleton-Provider.
This is how I tried to use the code above:
public class MyClass
{
public static IMyInterface Initialize()
{
if (Singleton<IMyInterface>.Instance == null // Error 1
{
Singleton<IMyInterface>.Instance = CreateEngineInstance(); // Error 2
Singleton<IMyInterface>.Instance.Initialize();
}
return Singleton<IMyInterface>.Instance;
}
}
And the interface:
public interface IMyInterface
{
}
The error at Error 1 is:
'MyProject.IMyInterace' must be a non-abstract type with a public parameterless constructor in order to use it as parameter 'T' in the generic type or method 'MyProject.Singleton<T>'
The error at Error 2 is:
Property or indexer 'MyProject.Singleton<MyProject.IMyInterface>.Instance' cannot be assigned to -- it is read only
How can I fix this so that it is in line with the 2 articles mentioned above? Any other ideas or suggestions are appreciated.
