Namespace in C# with Example

A namespace is a container of group related classes, structs, enums, interfaces, and other types. You can organize related classes in a specific namespace. Namespaces help avoid naming conflicts between types and provide a hierarchical structure for organizing your code.

Namspace in C# with Example

The below is syntax of declaring and use of namespace:

We use namespace keyword then give the name of namespace to writing a namespace.

Syntax of Namespace

namespace FruitNamespace
{
  // Types and members go here
}

Example

namespace FruitLibrary
{
  public class MangoUtils
  {
    public void GetFruitColor(string color)
    {
      return color;
    }
  }

  public class GraspeUtils
  {
    public void GetFruitColor(string color)
    {
      return color;
    }
  }
}

Using Directives:

To use types from a namespace in your code, you can add a using directive at the top of your C# file. This allows you to reference types from the namespace without specifying the full namespace each time.

Example

using FruitLibrary
class Program
{
  static void Main()
  {
    string result = MangoUtils.GetFruitColor("Yellow"); // Using MangoUtils from FruitLibrary
    Console.WriteLine(result)
  }
}

Nested Namespaces:

You can define a namespace within a another namespace and can create a hierarchical structure. This is useful for further organizing your code.

Example

namespace FruitApplication
{
  namespace MangoApplication
  {
    public class GreenMango
    {
      public void GetFruitColor(string color)
      {
        return color;
      }
    }
  }
}

To use types from nested namespaces, you can either use the full namespace path or include multiple using directives:

using FruitApplication.MangoApplication;
class Program
{
  static void Main()
  {
    string result = GreenMango.GetFruitColor("Green"); // Using MangoUtils from FruitLibrary
    Console.WriteLine(result)
  }
}

Global Namespace: