Moving a form only within a specified window

[Laveer]

Hello, I'm currently trying to make an extension to one of my programs which injects a .dll containing a form. I'd like to know if it's possible to have the form ( from the dll ) only be restricted to moving within the specified process's window.

[Laveer]

bump

[coder777]

what kind of window is it? normally a window should move according(=inside) to its parent