• Built in namespaces like system. When you are referring you need to use a key word like using.
  • e.g.. using System;
    using System.Collections.Generic;
    using System.Text;
• Start of your custom namespace

   {

  • Your class starts e.g. class do_something
    • {

      method or function starts

      {

      }

      method ends

    • }
  • Your class do_something
  • A class that stands as an Entry point

    public static void Main()

    {

                    your code that will retrieve output /work done by the other classes

    }

  }

•  End of your custom namespace

using System;
using System.Collections.Generic;
using System.Text;
//start with custom namespace
namespace string_maipulation
{
class stringhandler
{
public void joinarry()
{
Console.WriteLine("hello");
}
}
class Program
{
static void Main(string[] args)
{
stringhandler ss = new stringhandler();
ss.joinarry();
Console.ReadLine();

}
}
}//end of the namespace

• Declaration: A class is declared with a key word "class". The accessor "public" or private or protected should be the first one to begin with

public class test
{
    //Fields, properties, methods and events go here...
 // these are class members
}
 

• Instantiation:

    using System;
//compile csc class_object.cs
public class explain_class
{

public string str = "string variable in class";
public int n = 123456;
public explain_class() { Console.WriteLine("constructor Evoked ");}
~explain_class() { Console.WriteLine("destructor Evoked ");}
public void write()
{
Console.WriteLine(str);
}
}


class test2
{
public static void Main()
{
Console.WriteLine("Hello World");
// creating an instance and objects
explain_class ec1 = new explain_class();
//object ec is created with new key word.
// when you write explain_class ec; 
//an object is created without a refenece
// referencing object to object is allowed
explain_class ec2 = ec1;
//here ec1 and ec2 refer to the same object reference
///
//access a string variable with an object created from  explain_class 
Console.WriteLine("Acessing an sring variable :" + ec1.str);
// access a non static variable
Console.WriteLine("Acessing an Integer variable : " + ec1.n);
// access method using objects
ec1.write();
ec2.write();
}
}