create new object of type... seems like it a reference?

[jmrieman]

probably something really stupid but.... I have created a 2 classes

public class PegBoard
{
public int Status;
}
public class BFSPegBoardNode
{
public PegBoard[,] BFSBoard;
public int rowFrom;
public int colFrom;
}

I have created a new object of this type
BFSPegBoardNode CurrentNode = new BFSPegBoardNode ();
push it on a Queue
MyMoveQueue.Enq ueue(CurrentNod e);
then deQueue later on
CurrentNode = (BFSPegBoardNod e)(MyMoveQueue. Dequeue());

What is happening is that the objects that exist on the queue are being
changed when i edit CurrentNode

Keep in mind... i am looking at CurrentNode... Enqueueing... Still edit
CurrentNode... then trying to push a seaparate instance.. is this not how it
works? is the queue just a queue of pointers or is my object declaration
wrong?

[KH]

RE: create new object of type... seems like it a reference?

That's right - your queue contains pointers to the objects. In C# classes are
reference types, passed by reference, and structs are value types, passed by
value by defaut.


"jmrieman" wrote:
[color=blue]
> probably something really stupid but.... I have created a 2 classes
>
> public class PegBoard
> {
> public int Status;
> }
> public class BFSPegBoardNode
> {
> public PegBoard[,] BFSBoard;
> public int rowFrom;
> public int colFrom;
> }
>
> I have created a new object of this type
> BFSPegBoardNode CurrentNode = new BFSPegBoardNode ();
> push it on a Queue
> MyMoveQueue.Enq ueue(CurrentNod e);
> then deQueue later on
> CurrentNode = (BFSPegBoardNod e)(MyMoveQueue. Dequeue());
>
> What is happening is that the objects that exist on the queue are being
> changed when i edit CurrentNode
>
> Keep in mind... i am looking at CurrentNode... Enqueueing... Still edit
> CurrentNode... then trying to push a seaparate instance.. is this not how it
> works? is the queue just a queue of pointers or is my object declaration
> wrong?
>
>
>[/color]

[Jon Skeet [C# MVP]]

RE: create new object of type... seems like it a reference?

KH <KH@discussions .microsoft.com> wrote:[color=blue]
> That's right - your queue contains pointers to the objects. In C# classes are
> reference types, passed by reference, and structs are value types, passed by
> value by defaut.[/color]

No, reference type expressions are passed by value by default as well.
It's just that the value of a reference type expression is a reference.

See http://www.pobox.com/~skeet/csharp/parameters.html

--
Jon Skeet - <skeet@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too

[Jon Skeet [C# MVP]]

Re: create new object of type... seems like it a reference?

jmrieman <jmrieman@hottm ail.com> wrote:[color=blue]
> probably something really stupid but.... I have created a 2 classes
>
> public class PegBoard
> {
> public int Status;
> }
> public class BFSPegBoardNode
> {
> public PegBoard[,] BFSBoard;
> public int rowFrom;
> public int colFrom;
> }
>
> I have created a new object of this type
> BFSPegBoardNode CurrentNode = new BFSPegBoardNode ();
> push it on a Queue
> MyMoveQueue.Enq ueue(CurrentNod e);
> then deQueue later on
> CurrentNode = (BFSPegBoardNod e)(MyMoveQueue. Dequeue());
>
> What is happening is that the objects that exist on the queue are being
> changed when i edit CurrentNode
>
> Keep in mind... i am looking at CurrentNode... Enqueueing... Still edit
> CurrentNode... then trying to push a seaparate instance.. is this not how it
> works? is the queue just a queue of pointers or is my object declaration
> wrong?[/color]

The queue is a queue of references - all classes are reference types,
whereas structs are value types.

See http://www.pobox.com/~skeet/csharp/parameters.html and
http://www.pobox.com/~skeet/csharp/memory.html for a bit of discussion
around the subject. Some day I'll get round to writing an article just
on types themselves...

--
Jon Skeet - <skeet@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too