Structure of C# Program

 A C# program consists of the following parts −

 

·       Namespace declaration

·       A class

·       Class methods

·       Class attributes

·       A Main method

·       Statements and Expressions

·       Comments 

Ex: 

using System; 

namespace HelloWorldApplication {

   class HelloWorld {

      static void Main(string[] args) {

         /* my first program in C# */

         Console.WriteLine("Hello World");

         Console.ReadKey();

      }

   }

}

 

Explanation:

 

·       The first line of the program using System; - the using keyword is used to include the System namespace in the program. A program generally has multiple using statements.

 

·       The next line has the namespace declaration. A namespace is a collection of classes. The HelloWorldApplication namespace contains the class HelloWorld.

 

·       The next line has a class declaration, the class HelloWorld contains the data and method definitions that your program uses. Classes generally contain multiple methods.

·       Methods define the behavior of the class. However, the HelloWorld class has only one method Main.

 

·       The next line defines the Main method, which is the entry point for all C# programs. The Main method states what the class does when executed.

 

·       The next line /*...*/ is ignored by the compiler and it is put to add comments in the program.

 

·       The Main method specifies its behavior with the statement Console.WriteLine("Hello World");

 

·       WriteLine is a method of the Console class defined in the System namespace. This statement causes the message "Hello, World!" to be displayed on the screen.