[SOLVED] How from an Handle can I retrieve the component name?

How from an Handle can I retrieve the component name?

In my app, I catch all event via SetWindowsHookEx and when a user clicks on a button I retrieve an hwnd that I guess is the handle of the Tbutton.

typedef struct tagMSG {
  HWND   hwnd;
  UINT   message;
  WPARAM wParam;
  LPARAM lParam;
  DWORD  time;
  POINT  pt;
  DWORD  lPrivate;
} MSG, *P

Now how can I from this hwnd retrieve the button name (or better the Delphi object representing the button?).

Maybe I can also retrieve the component via the POINT pt; ?

Solution

You can use FindControl, which will retrieve the object instance if the window is created by a control that belongs to the same instance of the VCL that calls the function. Since Name is published in TComponent, you can access the property regardless of the actual class type.

Every windowed VCL control has its object instance address stored in the API window's property list, along with properties containing information of module address, process id, thread id. This makes it possible for the VCL to backtrack a control from the window it created.