From HWND to control

Question

Im using the FindWindow method from user32.dll to find a window and get the handle, but is it possible to get the form control from the handle? and the use it like an ordinary form? Example:

int myhwnd = FindWindow(null, "MyWindow");
form myform = SomeMagic.GetFormFromHandle(myhwnd);
myform.Visible = false;

or do I have to continue to use the methods in user32.dll to send a message to the window?

Answer 1

It's very difficult to wrap a Form class around Win32 window handle. There is no full fledged implementation provided by Microsoft. So, you have to use Native functions only to communicate with a given handle.

Answer 2

Have you tried Control.FromHandle()? Forms are (inherit from) Controls. If you hit a nested control, you'll have to search up through its parents until you hit your Form.

This assumes there actually is a Form somewhere, and you've just used the user32 methods to locate its HWND.

Answer 3

If the window belongs to your application you can use Control.FromHandle Method. Otherwise you will have to continue using win api. For example to hide the window you need to call ShowWindow Function.

Answer 4

If it's a managed window (you've created it with System.Windows.Forms, and it has inherited from System.Windows.Forms.Control) you can get a reference to the Control object with

Control.FromHandle(myIntPtr);

Then you just get the parent of the control until you get the form.

If not, you can't get a Control object, what you can do though is to is to create a NativeWindow, and assign the IntPtr handle to the object with the AssignHandle. That will at least give you some access to the WndProc, and similar, but that's it.