Constructors

Constructors

Constructor is a special method which is invoked automatically at the time of object creation. The advantage of a constructor, is that it is called when an object of a class is created. It can be used to set initial values for fields

Constructor of a class must have the same name as the class name in which it resides.

A class can have any number of constructors.

Constructors save time,it help reducing the amount of code.

Types of Constructor

• Default constructor
• Parameterized constructor

Default constructor

A constructor with no parameters is called a default constructor.

using System;  
   public class Student 
    {  
        public Student()  
        {  
            Console.WriteLine("Default Constructor Called");  
        }  
        public static void Main(string[] args)  
        {  
            Student s1 = new Student();  
            Student s2 = new Student();  
        }  
    } 

OUTPUT

Default Constructor Called
Default Constructor Called

Parameterized constructor

Constructors can also take parameters, which is used to initialize fields. It is used to provide different values to distinct objects.

using System;  
   public class Student  
    {  
        public int rollno;   
        public String name;  
        public float marks;  
        public Student(int r, String n,float m)  
        {  
            rollno = r;  
            name = n;  
            marks = m;  
        }  
        public void display()  
        {  
            Console.WriteLine(rollno + " " + name+" "+ marks);  
        }  
   }  
   class TestStudent{  
       public static void Main(string[] args)  
        {  
            Student s1 = new Student(1, "Sonu", 67.3f);  
            Student s2 = new Student(2, "Monu", 89f);  
            s1.display();  
            s2.display();  
  
        }  
    }  

OUTPUT

1 Sonu 67.3
2 Monu 89