C# Programming - Classes and Objects

class Student s1, s2; // Here 'Student' is a user-defined class.
s1 = new Student(); 
s2 = new Student();

class Sample
{
    private int i;
    public Single j;
    private void DisplayData()
    {
        Console.WriteLine(i + " " + j);
    }
    public void ShowData()
    {
        Console.WriteLine(i + " " + j);
    }
}

1. Instance members of a class can be accessed only through an object of that class.
2. A class can contain only instance data and instance member function.
3. All objects created from a class will occupy equal number of bytes in memory.
4. A class can contain Friend functions.
5. A class is a blueprint or a template according to which objects are created.

1. Sample s = new Sample();
2. Sample s;
3. Sample s; s = new Sample();
4. s = new Sample();