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Contains  
Method  
Returns true if the current Queue contains the given Value
Queue Class
System.Collections NameSpace
CF1.  Function Contains ( Value : Object; ) : Boolean;
CF : Methods with this mark are Compact Framework Compatible
Description
The Contains method searches the current Queue for an entry matching Value, returning true if found, otherwise false.
Microsoft MSDN Links
System.Collections
System.Collections.Queue
 
 
A simple example
// Full Unit code.
// -------------------------------------------------------------
// Create a new WinForm application, double click the form to
// create an OnLoad event, and then replace the WinForm unit
// with this text.
 
unit WinForm;
 
interface
 
uses
  System.Drawing, System.Collections, System.ComponentModel,
System.Windows.Forms, System.Data;
 
type
  TWinForm = class(System.Windows.Forms.Form)
  \{REGION 'Designer Managed Code'\} // Note that REGION and ENREGION should be prefixed by a dollar sign
  strict private
    ///
    /// Required designer variable.
    ///

    Components: System.ComponentModel.Container;
    ///
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    ///

    procedure InitializeComponent;
    procedure TWinForm_Load(sender: System.Object; e: System.EventArgs);
  {ENDREGION}
  strict protected
    ///
    /// Clean up any resources being used.
    ///

    procedure Dispose(Disposing: Boolean); override;
  private
    { Private Declarations }
  public
    constructor Create;
  end;
 
  [assembly: RuntimeRequiredAttribute(TypeOf(TWinForm))]
 
implementation
 
\{REGION 'Windows Form Designer generated code'\}
///
/// Required method for Designer support -- do not modify
/// the contents of this method with the code editor.
///

 
 
procedure TWinForm.InitializeComponent;
begin
  //
  // TWinForm
  //
  Self.AutoScaleBaseSize := System.Drawing.Size.Create(5, 13);
  Self.ClientSize := System.Drawing.Size.Create(292, 266);
  Self.Name := 'TWinForm';
  Self.Text := 'WinForm';
  Include(Self.Load, Self.TWinForm_Load);
end;
{ENDREGION}
 
procedure TWinForm.Dispose(Disposing: Boolean);
begin
  if Disposing then
  begin
    if Components <> nil then
      Components.Dispose();
  end;
  inherited Dispose(Disposing);
end;
 
constructor TWinForm.Create;
begin
  inherited Create;
  //
  // Required for Windows Form Designer support
  //
  InitializeComponent;
  //
  // TODO: Add any constructor code after InitializeComponent call
  //
end;
 
procedure TWinForm.TWinForm_Load(sender: System.Object; e: System.EventArgs);
program Project1;
{$APPTYPE CONSOLE}

uses
  System.Collections;

var
  MyQueue    : System.Collections.Queue;
  Enumerator : IEnumerator;

begin
  // Create our queue
  MyQueue := Queue.Create;

  // Add entries to the queue
  MyQueue.EnQueue('First');
  MyQueue.EnQueue('Second');
  MyQueue.Enqueue('Third');

  // Display the queue
  Enumerator := MyQueue.GetEnumerator;
  while enumerator.MoveNext do
    Console.WriteLine(Enumerator.Current.ToString);

  Console.WriteLine;

  if MyQueue.Contains('Second')
  then Console.WriteLine('MyQueue contains ''Second''')
  else Console.WriteLine('MyQueue does not contain ''Second''');

  if MyQueue.Contains('Fourth')
  then Console.WriteLine('MyQueue contains ''Fourth''')
  else Console.WriteLine('MyQueue does not contain ''Fourth''');

  Console.Readline;
end.
 
end.
Hide full unit code
  First
  Second
  Third
  
  MyQueue contains 'Second'
  MyQueue does not contain 'Fourth'
 
 
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