Sal's RuneScape Forum > Constructors? C# Question

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Roy

Aug 18 2009, 04:46 PM

What are constructors and destructors, what do they do and are they really necessary?

Note: if possible no links to some tutorial unless it really explains it good...

cjgone

Aug 19 2009, 11:43 PM

They allow you to create objects of a specific type... I don't do C#, but if you've ever done Java, it would be like:

CODE

Box blah = new Box( 10,20,30,40); // create a new object box

public class Box {

public Box ( int x, int y, int x2, int y2)
{
//constructor code here
}
}

Never used a deconstructor, so I dunno how to use it. I'm guessing it allows you to delete the object. Just a guess.

Kaibamanjrs

Aug 20 2009, 05:18 AM

Constructors are instructions that should be run when an instance of the parent class is created.

For example, if i had this (public MyObjectType is our constructor)

CODE

class MyObjectType {
private int x;
private int y;
public MyObjectType (int x1, int y1) {
x = x1;
y= y1;
}
public void DoSomeCalculation () {
Console.WriteLine("This is my text" + x + y);
}
}

and then somewhere else I did this

CODE

MyObjectType myInstance = new MyObjectType (20,40);
myInstance.DoSomeCalculation ();

I should get
This is my text2040

I might have made an error somewhere, but this is basically how it works.

As for destructors, they are used for garbage collecting. When it is deemed necessary to get rid of it ( it runs out of scope or something) you could have special cleanup instructions in a destructor (which would be ~ followed by the name of your constructor) you must have a constructor if you have a destructor.

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