Represents a simple last-in-first-out (LIFO) non-generic collection of objects.
(in mscorlib.dll)
Visual Basic (Declaration)
<SerializableAttribute> _
<ComVisibleAttribute(True)> _
Public Class Stack _
Implements ICollection, IEnumerable, ICloneable
[SerializableAttribute]
[ComVisibleAttribute(true)]
public class Stack : ICollection, IEnumerable,
ICloneable
[SerializableAttribute]
[ComVisibleAttribute(true)]
public ref class Stack : ICollection, IEnumerable,
ICloneable
public class Stack implements ICollection, IEnumerable, ICloneable
For the generic version of this collection, see System.Collections.Generic..::.Stack<(Of <(T>)>).
Stack is implemented as a circular buffer.
The capacity of a Stack is the number of elements the Stack can hold. As elements are added to a Stack, the capacity is automatically increased as required through reallocation.
If Count is less than the capacity of the stack, Push is an O(1) operation. If the capacity needs to be increased to accommodate the new element, Push becomes an O(n) operation, where n is Count. Pop is an O(1) operation.
Stack accepts nullNothingnullptra null reference (Nothing in Visual Basic) as a valid value and allows duplicate elements.
The following example shows how to create and add values to a Stack and how to print out its values.
Imports System
Imports System.Collections
Imports Microsoft.VisualBasic
Public Class SamplesStack
Public Shared Sub Main()
' Creates and initializes a new Stack.
Dim myStack As New Stack()
myStack.Push("Hello")
myStack.Push("World")
myStack.Push("!")
' Displays the properties and values of the Stack.
Console.WriteLine("myStack")
Console.WriteLine(ControlChars.Tab & "Count: {0}", myStack.Count)
Console.Write(ControlChars.Tab & "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 'PrintValues
End Class
' This code produces the following output.
'
' myStack
' Count: 3
' Values: ! World Hello
using System;
using System.Collections;
public class SamplesStack {
public static void Main() {
// Creates and initializes a new Stack.
Stack myStack = new Stack();
myStack.Push("Hello");
myStack.Push("World");
myStack.Push("!");
// Displays the properties and values of the Stack.
Console.WriteLine( "myStack" );
Console.WriteLine( "\tCount: {0}", myStack.Count );
Console.Write( "\tValues:" );
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.
myStack
Count: 3
Values: ! World Hello
*/
using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myCollection );
int main()
{
// Creates and initializes a new Stack.
Stack^ myStack = gcnew Stack;
myStack->Push( "Hello" );
myStack->Push( "World" );
myStack->Push( "!" );
// Displays the properties and values of the Stack.
Console::WriteLine( "myStack" );
Console::WriteLine( "\tCount: {0}", myStack->Count );
Console::Write( "\tValues:" );
PrintValues( myStack );
}
void PrintValues( IEnumerable^ myCollection )
{
IEnumerator^ myEnum = myCollection->GetEnumerator();
while ( myEnum->MoveNext() )
{
Object^ obj = safe_cast<Object^>(myEnum->Current);
Console::Write( " {0}", obj );
}
Console::WriteLine();
}
/*
This code produces the following output.
myStack
Count: 3
Values: ! World Hello
*/
System..::.Object
System.Collections..::.Stack
Microsoft.VisualC..::.SymbolTableStack
Public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
To guarantee the thread safety of the Stack, all operations must be done through the wrapper returned by the Synchronized method.
Enumerating through a collection is intrinsically not a thread-safe procedure. Even when a collection is synchronized, other threads can still modify the collection, which causes the enumerator to throw an exception. To guarantee thread safety during enumeration, you can either lock the collection during the entire enumeration or catch the exceptions resulting from changes made by other threads.
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
.NET Compact Framework
Supported in: 3.5, 2.0, 1.0
XNA Framework
Supported in: 3.0, 2.0, 1.0
Reference