PrintScreen hook

#define BUILD_DLL
 
#include <windows.h>
#include "capture1.h"
 
LRESULT CALLBACK KeyboardProc(int code, WPARAM wParam, LPARAM lParam) {
   if(code < 0)
      return CallNextHookEx(NULL, code, wParam, lParam);
 
   if(wParam == VK_SNAPSHOT)
      return 1;
 
   else
      return 0;
}

#if defined BUILD_DLL
 
#define DLL_EXP __declspec(dllexport)
 
#else
 
#if defined BUILD_APP
#define DLL_EXP __declspec(dllimport)
#else
#define DLL_EXP
#endif
 
#endif

#define BUILD_APP
#include "capture1.h"

LRESULT CALLBACK KeyboardProc( int code, WPARAM wParam, LPARAM lParam )
{
        if (code < 0) return CallNextHookEx(NULL, code, wParam, lParam);
 
        KBDLLHOOKSTRUCT *pHookStruct = (KBDLLHOOKSTRUCT*)lParam;
 
        if (wParam == WM_KEYDOWN && pHookStruct->vkCode == VK_SNAPSHOT)
        {
                Form1->Memo1->Lines->Add("Íàæàòà êëàâèøà PrintScreen");
                // MessageBox нельзя выводить, ò.ê. ïðîöåäóðà äîëæна
                // áûñòðî îòðàáîòàòü
        }
 
        return CallNextHookEx(NULL, code, wParam, lParam);
}
 
HHOOK hHook;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
        hHook = SetWindowsHookEx(WH_KEYBOARD_LL, (HOOKPROC)KeyboardProc, HInstance, 0);
        if ( !hHook )
        {
                ShowMessage( "Error SetWindowsHookEx: " + SysErrorMessage(GetLastError()) );
        }
 
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::FormClose(TObject *Sender, TCloseAction &Action)
{
        if ( hHook )
        {
                if ( !UnhookWindowsHookEx(hHook) )
                {
                        ShowMessage( "Error UnhookWindowsHookEx: " + SysErrorMessage(GetLastError()) );
                }
        }
}

TImage *Fimg = new TImage (Application);
TJPEGImage *D_img = new TJPEGImage();
   if(Clipboard()->HasFormat(CF_BITMAP)) {
      try {
         Fimg->Picture->Bitmap->LoadFromClipboardFormat(CF_BITMAP, Clipboard()->GetAsHandle(CF_BITMAP), 0);
         D_img->Assign(Fimg->Picture->Bitmap);
         D_img->CompressionQuality=Tb_ql->Position;
         //D_img->Compress();
         D_img->SaveToFile("C:\\" + IntToStr(i) + ".jpg");
         //D_img->SaveToFile(Ed_path->Text + "sc_shot-" + Now().FormatString("hh-nn-ss") + ".jpg");
      }
      __finally {
         Beep();
         delete D_img;
         delete Fimg;
 
      }
   }

D_img->Assign(img->Picture->Bitmap);

LRESULT CALLBACK KeyboardProc( int code, WPARAM wParam, LPARAM lParam )
{
        static WPARAM wOldParam  = 0;
 
        if (code < 0) return CallNextHookEx(hHook, code, wParam, lParam);
 
        KBDLLHOOKSTRUCT *pHookStruct = (KBDLLHOOKSTRUCT*)lParam;
 
        if (pHookStruct->vkCode == VK_SNAPSHOT && wParam == WM_KEYDOWN && wOldParam != WM_KEYDOWN)
        {
                Form1->Memo1->Lines->Add("Íàæàòà êëàâèøà PrintScreen");
        }
 
        wOldParam = wParam;
 
        return CallNextHookEx(hHook, code, wParam, lParam);
}