Assembly: System (in system.dll)
The capacity of a Queue is the number of elements that the Queue can store. Count is the number of elements that are actually in the Queue.
The capacity is always greater than or equal to Count. If Count exceeds the capacity while adding elements, the capacity is increased by automatically reallocating the internal array before copying the old elements and adding the new elements.
Retrieving the value of this property is an O(1) operation.
The following code example demonstrates several properties and methods of the Queue generic class, including the Count property.
The code example creates a queue of strings with default capacity and uses the Enqueue method to queue five strings. The elements of the queue are enumerated, which does not change the state of the queue. The Dequeue method is used to dequeue the first string. The Peek method is used to look at the next item in the queue, and then the Dequeue method is used to dequeue it.
The ToArray method is used to create an array and copy the queue elements to it, then the array is passed to the Queue constructor that takes IEnumerable, creating a copy of the queue. The elements of the copy are displayed.
An array twice the size of the queue is created, and the CopyTo method is used to copy the array elements beginning at the middle of the array. The Queue constructor is used again to create a second copy of the queue containing three null elements at the beginning.
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter EditionThe Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.