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Queue::Clear Method

Removes all objects from the Queue.

Namespace:  System.Collections
Assembly:  mscorlib (in mscorlib.dll)

public:
virtual void Clear()

Count is set to zero, and references to other objects from elements of the collection are also released.

The capacity remains unchanged. To reset the capacity of the Queue, call TrimToSize. Trimming an empty Queue sets the capacity of the Queue to the default capacity.

This method is an O(n) operation, where n is Count.

The following example shows how to clear the values of the Queue.

using namespace System;
using namespace System::Collections;
void PrintValues( Queue^ myQ );
int main()
{

   // Creates and initializes a new Queue.
   Queue^ myQ = gcnew Queue;
   myQ->Enqueue( "The" );
   myQ->Enqueue( "quick" );
   myQ->Enqueue( "brown" );
   myQ->Enqueue( "fox" );
   myQ->Enqueue( "jumped" );

   // Displays the count and values of the Queue.
   Console::WriteLine( "Initially," );
   Console::WriteLine( "   Count    : {0}", myQ->Count );
   Console::Write( "   Values:" );
   PrintValues( myQ );

   // Clears the Queue.
   myQ->Clear();

   // Displays the count and values of the Queue.
   Console::WriteLine( "After Clear," );
   Console::WriteLine( "   Count    : {0}", myQ->Count );
   Console::Write( "   Values:" );
   PrintValues( myQ );
}

void PrintValues( Queue^ myQ )
{
   IEnumerator^ myEnum = myQ->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ myObj = safe_cast<Object^>(myEnum->Current);
      Console::Write( "    {0}", myObj );
   }

   Console::WriteLine();
}

/* 
 This code produces the following output.

 Initially,
    Count    : 5
    Values:    The    quick    brown    fox    jumped
 After Clear,
    Count    : 0
    Values:

 */

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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