c++builder 重载WindowProc、WndProc 截获消息，比Delphi多一个Message Map方法

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();
}

http://www.cnblogs.com/cb168/p/4705059.html