用Delphi编程实现清空回收站功能

发表于:2007-06-11来源:作者:点击数: 标签:
本程序演示如何通过程序来清空回收站。向窗体上添加一个TButton组件,它用于激活清空回收站的操作。 首先在程序的implementation段中定义3个常数和一个类型声明,代码如下: constSHERB_NOCONFIRMATION = $00000001 ;SHERB_NOPROGRESSUI = $00000002 ;SHERB_

本程序演示如何通过程序来清空回收站。向窗体上添加一个TButton组件,它用于激活清空回收站的操作。

首先在程序的implementation段中定义3个常数和一个类型声明,代码如下:

const
SHERB_NOCONFIRMATION = $00000001 ;
SHERB_NOPROGRESSUI = $00000002 ;
SHERB_NOSOUND = $00000004 ;
type
TSHEmptyRecycleBin=
function(Wnd:HWND;LPCTSTR:PChar;DWORD:Word):Integer;stdcall;


程序运行初期,程序首先会通过LoadLibrary函数加载动态链接库Shell32.dll,并且把加载后的操作句柄存储在LibHandle中。然后通过@SHEmptyRecycleBin:=GetProcAddress (LibHandle, ’SHEmptyRecycleBinA’)语句读取SHEmptyRecycleBinA函数的地址,如果以上语句能够正确执行(也就是@SHEmptyRecycleBin不等于nil),那么就调用SHEmptyRecycleBin完成清空回收站的操作。最后释放动态链接库。响应代码如下:
procedure TForm1.Button1Click(Sender: TObject);
var
 SHEmptyRecycleBin:TSHEmptyRecycleBin;
 LibHandle:THandle;
begin
 LibHandle := LoadLibrary(PChar(’Shell32.dll’)) ;
 if LibHandle <> 0 then
 begin
@SHEmptyRecycleBin := GetProcAddress(LibHandle, ’SHEmptyRecycleBinA’);
 end
 else
 begin
MessageDlg(’Failed to load Shell32.dll.’, mtError, [mbOK], 0);
Exit ;
 end ;
 if @SHEmptyRecycleBin <> nil then
 begin
SHEmptyRecycleBin(Application.Handle,’’,SHERB_NOCONFIRMATION or
SHERB_NOPROGRESSUI or SHERB_NOSOUND) ;
 end;
 FreeLibrary(LibHandle);
 @SHEmptyRecycleBin := nil ;
end; 
程序代码如下:
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
const
 SHERB_NOCONFIRMATION = $00000001 ;
 SHERB_NOPROGRESSUI = $00000002 ;
 SHERB_NOSOUND = $00000004 ;
type
 TSHEmptyRecycleBin=function(Wnd:HWND;LPCTSTR:PChar;DWORD:Word):Integer;stdcall;

 {$R *.dfm}
 procedure TForm1.Button1Click(Sender: TObject);
var
 SHEmptyRecycleBin:TSHEmptyRecycleBin;
 LibHandle:THandle;
begin
 LibHandle := LoadLibrary(PChar(’Shell32.dll’)) ;
 if LibHandle <> 0 then
 begin
@SHEmptyRecycleBin := GetProcAddress(LibHandle, ’SHEmptyRecycleBinA’);
 end
 else
 begin
MessageDlg(’Failed to load Shell32.dll.’, mtError, [mbOK], 0);
Exit ;
 end ;

 if @SHEmptyRecycleBin <> nil then
 begin
SHEmptyRecycleBin(Application.Handle,’’,
    SHERB_NOCONFIRMATION or SHERB_NOPROGRESSUI or SHERB_NOSOUND) ;
 end;
 FreeLibrary(LibHandle);
 @SHEmptyRecycleBin := nil ;
 end;
end.
(责任编辑:铭铭)

原文转自:http://www.ltesting.net

...