Queue

Question

Hi Can any one help me i am using queue class and i am is resizing by using TrimToSize(); how can i see that is it resized ....?

Vulpes · Answer

I thought I'd just see if I could get something to work using reflection. In the following program, we start with an empty queue with a capacity of 16. We then enqueue a couple of strings, call TrimToSize() and find that the capacity has now been reduced to 2: using System; using System.Collections; using System.Reflection; class Test { static void Main() { Queue q = new Queue(16); Type t = typeof(Queue); BindingFlags bf = BindingFlags.Instance | BindingFlags.NonPublic; FieldInfo fi = t.GetField ("_array", bf); object[] oa = (object[])fi.GetValue(q); Console.WriteLine(oa.Length); // 16 q.Enqueue("Hello"); q.Enqueue("World"); q.TrimToSize(); oa = (object[])fi.GetValue(q); Console.WriteLine(oa.Length); // 2 Console.ReadKey(); } }

Vulpes · Answer

There's no way to do this from 'normal' code as the Queue class doesn't have a Capacity property. You might be able to do it using reflection by obtaining the length of its private _array field which is an object[]. If you really need it, I could try to figure something out.

Queue

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