Queue

Implements:

Public:

Properties:

Name	Description
Count (get)	Gets the number of elements contained in the Queue.

Name

Description

Count (get)

Gets the number of elements contained in the Queue.

Methods:

Name	Description
Clear	Removes all items from the Queue.
Clone	Creates a shallow copy of the Queue.
Contains	Determines whether an element is in the Queue.
CopyTo	Copies the Queue elements to an existing one-dimensional array, starting at the specified array index.
Dequeue	Removes and returns the item at the beginning of the Queue.
Enqueue	Adds an item to the tail of the Queue, expanding the queue as necessary.
Equals	Returns a boolean indicating if the value and this object instance are the same instance.
GetEnumerator	Returns an enumerator for the queue.
GetHashCode	Returns a pseudo-unique number identifying this instance.
Peek	Returns the item at the beginning of the Queue without removing it.
ToArray	Copies the Queue elements to a new array.
ToString	Returns a string representation of this object instance.
TrimToSize	Sets the capacity to the actual number of elements in the Queue.

Name

Description

Clear

Removes all items from the Queue.

Clone

Creates a shallow copy of the Queue.

Contains

Determines whether an element is in the Queue.

CopyTo

Copies the Queue elements to an existing one-dimensional array, starting at the specified array index.

Dequeue

Removes and returns the item at the beginning of the Queue.

Enqueue

Adds an item to the tail of the Queue, expanding the queue as necessary.

Equals

Returns a boolean indicating if the value and this object instance are the same instance.

GetEnumerator

Returns an enumerator for the queue.

GetHashCode

Returns a pseudo-unique number identifying this instance.

Peek

Returns the item at the beginning of the Queue without removing it.

ToArray

Copies the Queue elements to a new array.

ToString

Returns a string representation of this object instance.

TrimToSize

Sets the capacity to the actual number of elements in the Queue.

Remarks

Queues are useful for storing messages in the order they were received for sequential processing. This class implements a queue as a circular array. Values stored in a Queue are inserted at one end and removed from the other.

The capacity of a Queue is the number of elements the Queue can hold. As elements are added to a Queue, the capacity is automatically increased as required through reallocation. The capacity can be decreased by calling TrimToSize.

Examples

The following example shows how to create and add values to a Queue and how to print out its values.

Public Sub Main()
    ' Creates and initializesa new Queue.
    Dim MyQ As New Queue
    MyQ.Enqueue "Hello"
    MyQ.Enqueue "World"
    MyQ.Enqueue "!"
    
    ' Displays the properties and values of the Queue.
    Debug.Print "MyQ"
    Debug.Print "    Count:    " & MyQ.Count
    Debug.Print "   Values:";
    PrintValues MyQ
End Sub

Private Sub PrintValues(ByVal MyCollection As IEnumerable)
    Dim Item As Variant
    
    For Each Item In MyCollection
        Debug.Print "    " & Item;
    Next
    
    Debug.Print
End Sub

' The example code produces the following output.
'
'    MyQ
'        Count:    3
'       Values:    Hello    World    !

ICloneable
ICollection
IEnumerable
IObject
IVersionable