How to use Global Variables in C#?

Question

How do I declare a variable so that every class (*.cs) can access its content, without an instance reference?

Answer 1

In C# you cannot define true global variables (in the sense that they don't belong to any class).

This being said, the simplest approach that I know to mimic this feature consists in using a static class, as follows:

public static class Globals
{
    public const Int32 BUFFER_SIZE = 512; // Unmodifiable
    public static String FILE_NAME = "Output.txt"; // Modifiable
    public static readonly String CODE_PREFIX = "US-"; // Unmodifiable
}

You can then retrieve the defined values anywhere in your code (provided it's part of the same namespace):

String code = Globals.CODE_PREFIX + value.ToString();

In order to deal with different namespaces, you can either:

• declare the Globals class without including it into a specific namespace (so that it will be placed in the global application namespace);
• insert the proper using directive for retrieving the variables from another namespace.