What is an instance of a class Red many definitions of a constructor But did not understand the exact working of a constructor What is the main use of constructor how it works?

Answer 1

The consttructor creates a new instance of the class

for example the class shown below does not exist until the constructor is called, where it sets the class up for first use.

Class Dog

{

int _legs, _eyes;

string _breed;

//CONSTRUCTOR, this takes an input from the user which sets the breed of the dog, and sets the default number of legs and eyes.

public Dog(input)

{

_legs = 4;

_eyes = 2;

_breed = input;

}

}

if the user calls the constructor with the string "Labrador", that is one instance of the class, if the user calls it again with the string "terrier" that is another instance. the class is constructed like this:

//Class instancename = New class(parameters);

Dog lab = New Dog("Labrador");

hope this helps

Steve