asked on

Queue Dequeue ArrayList Count 0?

I can successfully Enqueue ArrayList's to a Collections.Queue. Having problem Dequeue-ing ArrayList. I know the Queued ArrayLists contain data by running a foreach at myQueue.cs

[myQueue]

internal class myQueue
{
private static Queue que = Queue.Synchronized(new Queue());

internal static void Enque(ArrayList list)
{
que.Enqueue(list);
}

internal static ArrayList Deque()
{
return (ArrayList)que.Dequeue();
}
}

Every attempt to dequeue the queued ArrayList returns a count of 0, although I know the Queue definitely has ArrayList's queued.

[AnotherClass.cs]

ArrayList arr = new ArrayList(Que.Deque()); //count=0

ArrayList arr = new ArrayList(); arrData.AddRange(Que.Deque()); //count=0

ArrayList arr = Que.Deque();//count=0

ArrayList arr = (ArrayList)Que.Deque();//count=0

ArrayList arr = new ArrayList();
arr = Que.Deque();

Dmitry G

Honestly, I didn't understand, how you created your Queue in anotherclass, and what you have enqueued... Pls more details

ASKER CERTIFIED SOLUTION

Mike Tomlinson

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Dmitry G

Yeah, indeed... How Idle_Mind enques a list - I can see! :)

I believe the error in the original post - no lists were enqued!

pointeman

ASKER

I though it could be a threading issue, but change the Queue into a String and Dequeue works fine.

More details...

1. Windows Service project, NOT winform.
2. Class1.cs successfully Enqueues data to myQueue.cs
3. myQueue.cs successfully writes ArrayList data to logfile using foreach...
4 Class2 uses myQueue.Deque() Unsuccessfully

[Class1.cs]

ArrayList1 arrayList1 = new ArrayList();
arrayList1.add...........
myQueue.Enque(arrayList1);

[myQueue.cs]
internal class myQueue
{
private static Queue que = Queue.Synchronized(new Queue());

internal static void Enque(ArrayList list)
{
que.Enqueue(list);
}

internal static ArrayList Deque()
{
return (ArrayList)que.Dequeue();
}
}

[Class2.cs]
ArrayList al = myQueue.Deque();
foreach (Object o in al)
{
Console.WriteLine(o.ToString());
}

NOT returning any data, just count 0

Maybe this is a Windows Service & threading issue?

SOLUTION

Dmitry G

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Dmitry G

BTW, how you pass the queue object between classes?

pointeman

ASKER

Good point...

1. I use "MyQueue myQueue = new MyQueue" ONLY 1 time in entire project.
2. I instanciate ALL classes & threads in very 1st boot-up class (via service1 OnStart()).
2. Unusual that I can grab strings all day long, but cannot return the ArrayList.

Mike Tomlinson

Regarding #1, everything in myQueue is STATIC, so you don't need an instance of it.