Stack.Clear Method 
Definition
Important
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Removes all objects from the Stack.
public:
 virtual void Clear();public virtual void Clear();abstract member Clear : unit -> unit
override this.Clear : unit -> unitPublic Overridable Sub Clear ()Examples
The following example shows how to clear the values of the Stack.
using System;
using System.Collections;
public class SamplesStack  {
   public static void Main()  {
      // Creates and initializes a new Stack.
      Stack myStack = new Stack();
      myStack.Push( "The" );
      myStack.Push( "quick" );
      myStack.Push( "brown" );
      myStack.Push( "fox" );
      myStack.Push( "jumps" );
      // Displays the count and values of the Stack.
      Console.WriteLine( "Initially," );
      Console.WriteLine( "   Count    : {0}", myStack.Count );
      Console.Write( "   Values:" );
      PrintValues( myStack );
      // Clears the Stack.
      myStack.Clear();
      // Displays the count and values of the Stack.
      Console.WriteLine( "After Clear," );
      Console.WriteLine( "   Count    : {0}", myStack.Count );
      Console.Write( "   Values:" );
      PrintValues( myStack );
   }
   public static void PrintValues( IEnumerable myCollection )  {
      foreach ( Object obj in myCollection )
         Console.Write( "    {0}", obj );
      Console.WriteLine();
   }
}
/*
This code produces the following output.
Initially,
   Count    : 5
   Values:    jumps    fox    brown    quick    The
After Clear,
   Count    : 0
   Values:
*/
Imports System.Collections
Public Class SamplesStack    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new Stack.
        Dim myStack As New Stack()
        myStack.Push("The")
        myStack.Push("quick")
        myStack.Push("brown")
        myStack.Push("fox")
        myStack.Push("jumps")
        
        ' Displays the count and values of the Stack.
        Console.WriteLine("Initially,")
        Console.WriteLine("   Count    : {0}", myStack.Count)
        Console.Write("   Values:")
        PrintValues(myStack)
        
        ' Clears the Stack.
        myStack.Clear()
        
        ' Displays the count and values of the Stack.
        Console.WriteLine("After Clear,")
        Console.WriteLine("   Count    : {0}", myStack.Count)
        Console.Write("   Values:")
        PrintValues(myStack)
    End Sub    
    Public Shared Sub PrintValues(myCollection As IEnumerable)
        Dim obj As [Object]
        For Each obj In  myCollection
            Console.Write("    {0}", obj)
        Next obj
        Console.WriteLine()
    End Sub
End Class
' This code produces the following output.
' 
' Initially,
'    Count    : 5
'    Values:    jumps    fox    brown    quick    The
' After Clear,
'    Count    : 0
'    Values:
Remarks
Count is set to zero, and references to other objects from elements of the collection are also released.
This method is an O(n) operation, where n is Count.