How to locate important system directories

Using ShlObj unit and SHGetSpecialFolderLocation Windows API function, we can retrieve the location of a special folders, such as My computer, Desktop, Program Files etc… There are over 20 special folder locations.

To get more info about SHGetSpecialFolderLocation, visit MSDN pages. As you can see below, the source code is very simple. The most important thing is CSIDL value, that identifies the folder of interest. Here is a small list of these values (names are self-explaining):

CSIDL_DESKTOP CSIDL_INTERNET CSIDL_PROGRAMS CSIDL_CONTROLS CSIDL_PRINTERS CSIDL_PERSONAL CSIDL_FAVORITES CSIDL_STARTUP CSIDL_RECENT CSIDL_SENDTO CSIDL_BITBUCKET CSIDL_STARTMENU CSIDL_DESKTOPDIRECTORY CSIDL_DRIVES CSIDL_NETWORK CSIDL_NETHOOD CSIDL_FONTS CSIDL_TEMPLATES CSIDL_COMMON_STARTMENU CSIDL_COMMON_PROGRAMS CSIDL_COMMON_STARTUP CSIDL_COMMON_DESKTOPDIRECTORY CSIDL_APPDATA CSIDL_PRINTHOOD CSIDL_ALTSTARTUP CSIDL_COMMON_ALTSTARTUP CSIDL_COMMON_FAVORITES CSIDL_INTERNET_CACHE CSIDL_COOKIES CSIDL_HISTORY

The code below shows how to retrieve History folder.

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
  pidl: PItemIDList;
  path: array[0..MAX_PATH] of char;
begin
  SHGetSpecialFolderLocation(Handle, CSIDL_HISTORY, pidl);
  SHGetPathFromIDList(pidl, path);
  ShowMessage(path);
end;

end.

Leave a Reply Cancel reply