重载WindowProc、WndProc

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方法一WindowProc

void __fastcall myWindowProc(Messages::TMessage &Message); //增加
Classes::TWndMethod OldWindowProc; //增加

void __fastcall TForm1::myWindowProc(Messages::TMessage &Message)
{
   if (Message.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 &Message);
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 &Message)
{
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 &Message);

void __fastcall TForm1::WndProc(Messages::TMessage &Message)
{
if (Message.Msg == WM_MOUSEWHEEL && Message.WParam )
    {
      Caption = Now();
    }
    TForm::WndProc(Message);
}