The classic approach to creating a Singleton looks like this:

public class SingletonGamma
 {
      private static SingletonGamma instance;
      private SingletonGamma()  { }

      public static SingletonGamma Instance
     {
         get 

         {
            if (instance == null) { instance = new SingletonGamma(); }
            return instance;
         }
     }
 } 

The basic approach is  to create a private constructor and an Instance method that returns the current instance if available, or returns a new instance if there is no current instance. We call that "lazy instantiation". The problem with this approach in C# is that it is not strictly thread-safe. That is, it is possible for 2 threads to create separate instances is some circumstances. This is not what we are looking to do. This approach does have an advantage in that there is a hook-point to do post-instantiation processing if required. In .Net though, this is not the approach usually recommended

The following example takes advantage of the better handling of variable ambiguity in .Net (vs. C++) to create a thread-safe Singleton:

public sealed class SingletonCSharp
    {
        private static readonly Singleton instance = new SingletonCSharp();

        private SingletonCSharp() { }

        public static SingletonCSharp Instance
        {
            get
            {
                return instance;
            }
        }
    }

This is the preferred approach in C# and is adequate for most programs. There are other approaches that allow for more flexibility and still maintain thread safety, but they introduce unnecessary complexity for most programs. Note the read only instance property that can only be set during instantiation and the sealed keyword that prevents inheritance of the class which could introduce unwanted side effects, such as secondary instances. This is a simple and straightforward approach to the design pattern. The only downside is the lack of flexibility to have non-standard constructors. For most applications, that will not be an issue.

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Here’s how to do it:

1. Create a new folder.
2. Rename the folder to GodMode.{ED7BA470-8E54-465E-825C-99712043E01C}(note that you can change the “GodMode” text, but the following period and code number are essential).
3. The folder icon will change to  — double click it to show the GodMode window.
   

The image below shows what you see in the GodMode window. There a host of links to utilities and settings. Having them all in one place is extremely convenient. This secret trick appears to work in Windows 7 32 and 64 bit, Windows Server 2008 32 bit and Vista 32 bit. BUT, it seems to crash Vista 64 bit. You have been warned

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