Queue.Clear Method

Definition

Namespace:

System.Collections

Assemblies:

netstandard.dll, System.Collections.NonGeneric.dll

Source:

Queue.cs

Removes all objects from the Queue.

C#

public virtual void Clear();

Examples

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

C#

using System;
using System.Collections;
public class SamplesQueue  {

   public static void Main()  {

      // Creates and initializes a new Queue.
      Queue myQ = new Queue();
      myQ.Enqueue( "The" );
      myQ.Enqueue( "quick" );
      myQ.Enqueue( "brown" );
      myQ.Enqueue( "fox" );
      myQ.Enqueue( "jumps" );

      // 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 );
   }

   public static void PrintValues( Queue myQ )  {
      foreach ( Object myObj in myQ )  {
         Console.Write( "    {0}", myObj );
      }
      Console.WriteLine();
   }
}
/*
This code produces the following output.

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

*/

Remarks

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.

Applies to

See also

• TrimToSize()