查找当前所有顶级窗口

有时常需要查找当前有哪些窗口打开着，所以先用一种方法写下来：

效果：

//工程文件
program Project1;

uses
  Forms,
  Unit1 in 'Unit1.pas' {Form1};

{$R *.res}

begin
  Application.Initialize;
  Application.MainFormOnTaskbar := True;
  Application.CreateForm(TForm1, Form1);
  Application.Run;
end.

// 单元文件
unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    ListBox1: TListBox;
    Label1: TLabel;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    procedure ListBox1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

  function EnumWindowsProc(hwnd: HWND; lparam: Integer): Boolean ; stdcall;

var
  Form1: TForm1;
  slist: TStringList;

implementation

{$R *.dfm}

procedure TForm1.Button2Click(Sender: TObject);
begin
  ListBox1.Clear;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  slist := TStringList.Create;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  slist.Free;
end;

procedure TForm1.ListBox1Click(Sender: TObject);
begin
  SetWindowText(Handle,ListBox1.Items[ListBox1.ItemIndex]);
end;

function EnumWindowsProc(hwnd: HWND; lparam: Integer):Boolean;
var
  buf: array[Byte] of char;
  swnd: string;
begin
  GetWindowText(hwnd, buf, sizeof(buf)); //取得窗口标题
  swnd := Inttostr(hwnd);
  slist.Add('窗口句柄：'+swnd +'---'+'标题：'+ buf);
  Result := True;    //重要
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  EnumWindows(@EnumWindowsProc, 0);
  ListBox1.Items.Assign(slist);
end;

end.

//窗体代码
object Form1: TForm1
  Left = 0
  Top = 0
  BorderIcons = [biSystemMenu, biMinimize]
  Caption = 'Form1'
  ClientHeight = 295
  ClientWidth = 448
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  Position = poScreenCenter
  OnCreate = FormCreate
  OnDestroy = FormDestroy
  PixelsPerInch = 96
  TextHeight = 13
  object Label1: TLabel
    Left = 8
    Top = 8
    Width = 121
    Height = 18
    AutoSize = False
    Caption = #24403#21069#30340#39030#23618#31383#21475#26377#65306
  end
  object Button1: TButton
    Left = 352
    Top = 48
    Width = 75
    Height = 41
    Caption = #26597#25214
    TabOrder = 0
    OnClick = Button1Click
  end
  object ListBox1: TListBox
    Left = 8
    Top = 32
    Width = 298
    Height = 257
    ItemHeight = 13
    TabOrder = 1
    OnClick = ListBox1Click
  end
  object Button2: TButton
    Left = 352
    Top = 184
    Width = 75
    Height = 41
    Caption = #28165#31354
    TabOrder = 2
    OnClick = Button2Click
  end
end