一. 捕获别人给自己发来的消息:
既然是挂钩QQ的消息框,自然得从众多的钩子类型中找出一种最为合理,也最方便的.很容易想到的是无论你用什么方式查看QQ的消息.总会导致一个QQ消息窗体的生成.就是会产生一个CREATE事件.从这一点上看,用一个WH_SHELL钩子是比较明智的.
帮助上对WH_SHELL的说明是:监控Windows外壳通知消息,例如顶级窗口的创建的释放.我们这里要关心是窗口的创建消息.
由于有可能一次出现多个QQ消息窗口的情况,我在这里使用全局钩子:并定义以下数据结构:
HookType.Pas单元
unit HookType;
interface
uses
Windows, Messages;
const
WM_USERCMD = WM_APP + 1; //用户自定应用程序级消息
UC_WINCREATE = WM_APP + 2; //QQ消息窗口创建
UC_WINDESTROY = WM_APP + 3; //发送QQ消息
BUFFER_SIZE = 16 * 1024;
HOOK_MEM_FILENAME = 'MEM_FILE';
type
TShared = record
KeyHook : HHook; //键盘钩子
ShellHook: HHook;
CallHook : HHook;
MainWnd : THandle; //窗体的Handle(非Application.Handle)
Moudle : THandle; //DLL
end;
PShared = ^TShared;
implementation
end.
DLL单元代码
var
MemFile: THandle;
Shared: PShared;
function ShellProc(iCode: Integer; wParam: WPARAM; lParam: LPARAM): LRESULT; stdcall;
begin
case iCode of
HSHELL_WINDOWCREATED:
//有顶级窗口创建时向演示程序发送自己定义消息WM_USERCMD. Wparamr参数说明
// wParam specifies the handle of the window being created or destroyed, respectively.
PostMessage(Shared^.MainWnd,WM_USERCMD ,UC_WINCREATE,wParam);
end;
Result := CallNextHookEx(Shared^.ShellHook,iCode,wParam,lParam);
end;
function InstallHook:Boolean;
begin
Shared^.Moudle:=GetModuleHandle(PChar('qqhook')); //qqhook是我的DLL文件名.
Shared^.ShellHook := SetWindowsHookEx(WH_SHELL,
@ShellProc,
Shared^.Moudle,
0);
if Shared^.ShellHook = 0 then
begin
Result := False;
Exit;
end;
Result := true;
end;
{撤消钩子过滤函数}
function UninstallHook: Boolean;
begin
Freelibrary(Shared^.Moudle);
Result:=UnHookWindowsHookEx(Shared^.ShellHook);
UnmapViewOfFile(Shared);
CloseHandle(memFile);
end;
procedure DllEntry(dwReason : integer);
begin
case dwReason Of
DLL_PROCESS_ATTACH:
begin
MemFile:= OpenFileMapping(FILE_MAP_WRITE,False,HOOK_MEM_FILENAME);
if MemFile = 0 then
MemFile := CreateFileMapping($FFFFFFFF,nil,
PAGE_READWRITE,
0,
SizeOf(TShared),
HOOK_MEM_FILENAME);
Shared := MapViewOfFile(MemFile,
File_MAP_WRITE,
0,
0,
0);
end;
DLL_PROCESS_DETACH:
begin
//UninstallHook;
end;
else;
end;
end;
exports
InstallHook;
begin
DllProc := @DllEntry;
DllEntry(DLL_PROCESS_ATTACH);
end.
//上述代码对卸载钩子没有加太多说明,它不属于此范围讨论之内.
演示程序代码
procedure TForm1.Button1Click(Sender: TObject);
begin
InstallHook;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
MemFile:= OpenFileMapping(FILE_MAP_WRITE,False,HOOK_MEM_FILENAME);
if MemFile = 0 then
MemFile := CreateFileMapping($FFFFFFFF,nil,
PAGE_READWRITE,
0,
SizeOf(TShared),
HOOK_MEM_FILENAME);
Shared := MapViewOfFile(MemFile,
File_MAP_WRITE,
0,
0,
0);
Shared^.MainWnd := Handle; //保存窗体句柄
end;
//窗口消息处理过程
procedure TForm1.WndProc(var Msg: TMessage);
begin
with Msg do
begin
if Msg = WM_USERCMD then //DLL发来的自定义消息
begin
case wParam of
UC_WINCREATE : //QQ消息框创建
begin
GetText(Findhwd(HWND(lParam))); //得到QQ消息框里的文本
end;
end;
end;
end;
inherited;
end;
//通过wParam参数找到QQ窗口句柄
function TForm1.Findhwd(parent: HWND):HWND;
var
hwd,hBtn,hMemo:HWND;
begin
result := 0;
hwd:=findwindowex(parent,0,'#32770',nil); //QQ次级窗口句柄QQ2003及以前版本没有此项.
if (hwd<>0) then
begin
hBtn := FindwindowEX(hwd,0,nil,'回讯息(&R)'); //可以以此来证明是收到的QQ消息框.
if (hBtn<>0) then
begin
hMemo := GetDlgItem(hwd,$00000380); //RichEdit的句柄,QQ消息就存在于此处.
if (hMemo<>0) then
result := hMemo;
end;
end;
end;
//得到指定句柄控件中的文本.
procedure TForm1.GetText(hwd: HWND);
var
Ret: LongInt;
QQText: PChar;
Buf: integer;
begin
GetMem(QQText,1024);
if (hwd<>0) then
begin
try
Ret := SendMessage(hwd, WM_GETTEXTLENGTH, 0, 0) + 1;
Buf := LongInt(QQText);
SendMessage(hwd, WM_GETTEXT, Min(Ret, 1024), Buf);
memo1.Lines.Add(QQText); //在Memo中显示文本
finally
FreeMem(QQText, 1024);
end;
end;
end;
以上是我测试时的代码,只是为了分类阐述的方便,才帖出来.也许还有些不合理的地方. 若这里有什么不详尽之处,在下篇将提供完整代码下载.
hottey于2005-6-2 网站:http://asp.itdrp.com/hottey
