Learn C# programming / PDF

 Learn c# programming / PDF

Structure of a C# program

For the first program, below listing shows the near-minimal amount of code necessary to write.

/*

  File name :  FirstProgram.cs

  Author :Ali Can

*/

using System;

// Program start class

public Class FirstProgram

{

      public static void main()

{

Console.WriteLine(“This Is My First C# Program “);

}

      }

A  simple C# program consist of the following structures.

• contains classes, structures and types.
•  A class has

o   Data(fields)

o   Behaviors(methods)

• A C# application can consist of many files
• Have a Main method as an entry point
• The .NET Framework provides many classes which are organized in namespaces
• Most common namespace is System
• Refer to classes by their namespace
• Namespaces must be fully qualified without Using directive

System.Console.WriteLine(“This My First C# Program “);

Using directive allows for less typing

using System;

…

Console.WriteLine(“This My First C# Program “);

C# uses class to define or declare objects. They describe the attributes and behavior of an object. An object is anything that has attributes and behavior. Objects are building blocks of the C# programming language. It has a starting object.

The identifier, or name , of a class follows the class keyword. This is called  FirstProgram.

Left and right braces indicate the beginning and ending, respectively of a block.

There is a method declaration in the given program. This is Main() method. Every program has a Main() method that is the starting point for the program. C# Main() methods always have static modifier. In C# there are two types of objects:

Static

instance.

Instance objects are formally declared, and there can be many of the same type with different attributes.

However , there can be only a single copy of static object  in existence for a given program. The only way to execute a method without an instance of its containing object is if that method is static.

The Console class enables programs to output information to the computer’s standard output. Class Console provides methods that allow C# programs to display strings and other types of information in the Windows command prompt.

Method Console.WriteLine displays a line of text in the console window, its argument in the parentheses (“This is My First C# Program”) and the semicolon (;) is called statement.

Identifiers and keywords

Identifiers are names of various program elements in the code that uniquely identify an element. They are name of things like variables or fields.

There are essentially two forms of naming conventions in C#.

The first is pascal casing, where the first letter of each word in a name is capitalized, such as

HelloWorld

PersonelNumber.

Pascal casing is normally used in all instance except for parameters and private fields of classes.

In the case of private class fields and method parameters, use camel casing , where the first letter of the first word is lowercase and the first letter of subsequent words is capitalized............

 Learn c# programming / PDF