unit1.pas

Delphi实效编程百例的随书源代码 这是其中的磁盘文件部分

unit Unit1;

interface

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

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

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure EmptyRecycleBin;
{ proc to empty the recycle bin. }
const
  SHERB_NOCONFIRMATION = $00000001;
  SHERB_NOPROGRESSUI = $00000002;
  SHERB_NOSOUND = $00000004;
type
  TSHEmptyRecycleBin = function (Wnd: HWND;LPCTSTR: PChar;
                                 DWORD: Word): integer; stdcall;
var
  SHEmptyRecycleBin: TSHEmptyRecycleBin;
  LibHandle: THandle;
begin
  LibHandle := LoadLibrary(PChar('Shell32.dll'));
  //加载shell32.dll中的函数
  if LibHandle <> 0 then
  //取得回收站的句柄
    @SHEmptyRecycleBin := GetProcAddress(LibHandle, 'SHEmptyRecycleBinA')
  else
  begin
       MessageDlg('不能加载文件Shell32.dll.', mtError, [mbOK], 0);
       Exit;
  end;

  if @SHEmptyRecycleBin <> nil then
     SHEmptyRecycleBin(Application.Handle,'',SHERB_NOCONFIRMATION or
     SHERB_NOPROGRESSUI or SHERB_NOSOUND);
  FreeLibrary(LibHandle);
  @SHEmptyRecycleBin := nil;
  //清空回收站
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  if MessageDlg('确认要删除回收站中的内容吗？',
    mtConfirmation, [mbYes, mbNo], 0) = mrYes then
  begin
     EmptyRecycleBin;
  end;
end;

end.