c++builder 重载WindowProc、WndProc 截获消息 

方法一WindowProc

void __fastcall  myWindowProc(Messages::TMessage &msg); //增加

Classes::TWndMethod OldWindowProc;  //增加

 

void __fastcall  TForm1::myWindowProc(Messages::TMessage &msg)

 {

   if (msg.Msg == WM_MOUSEWHEEL)

   {

     //::MessageBox(NULL,"OK","Message",0);  //测试

     Caption = Now();

   }

   else

     OldWindowProc(Message);

 }

void __fastcall TForm1::FormCreate(TObject *Sender)

{

  OldWindowProc=Edit1->WindowProc;

  Edit1->WindowProc=myWindowProc;        

}

方法二 MESSAGE_MAP

class TForm1 : public TForm

{

__published: // IDE-managed Components

        TEdit *Edit1;

private: // User declarations

void __fastcall OnEditMouseWell(TMessage &msg);

BEGIN_MESSAGE_MAP 

MESSAGE_HANDLER(WM_MOUSEWHEEL, TMessage, OnEditMouseWell)

END_MESSAGE_MAP(TForm)  //TForm 换成TEdit 

public:  // User declarations

        __fastcall TForm1(TComponent* Owner);

};

 void __fastcall TForm1::OnEditMouseWell(TMessage &msg)

 {

   if(String(ActiveControl->ClassName())=="TEdit")  //所有的Edit

      Caption   = Now(); //测试

//TForm::Dispatch(&Msg); 

}

方法三 重载 WndProc

private: // User declarations

     void __fastcall WndProc(Messages::TMessage &msg);

 

void __fastcall TForm1::WndProc(Messages::TMessage &msg)

{

  if (msgMsg == WM_MOUSEWHEEL && msg.WParam )

    {

      Caption = Now();

    }

    TForm::WndProc(msg);

}

四、ApplicationEvents控件

 窗体上放置ApplicationEvents1控件，在ApplicationEvents1Message事件里判断。

void __fastcall TForm3::ApplicationEvents1Message(tagMSG &Msg, bool &Handled){    if (Msg.hwnd == this->DBGrid1->Handle && Msg.message == WM_MOUSEWHEEL)        this->Caption = Now();}

 

WM_LBUTTONDOWN