how to convert Inptr into HWND

[r00d0034]

if i have hwndle (Intptr)of parent window and hwndle of child window then how to get the point and rectangle of child window with respect to its parent window ?

how to convert HWND into intptr?

[sammyh]

I'm having the opposite problem, I need to convert an IntPtr to an HWND..... Any suggestions. Thanks

-Sam

[Sput]

I don't know a lot about .NET yet, but why would you want to convert from an IntPtr to and HWND? In .NET, an hwnd is an IntPtr.

So, let me take a guess....

For Instance, in the expression: Graphics newGraphic = Graphics.FromHwnd(hWnd)

the hWnd is actually an IntPtr that can come from something like myForm.Handle().

Is it because you are trying to use UnManaged code passing it a managed hWnd (or IntPtr) ?


Anyways, to convert to an SDK's version of an HWND, one theory (without any testing!!) would be: HWND hWnd = (HWND)MyIntPtr.ToInt32().

I also couldn't find any nice methods to convert a .NET hWnd to an SDK's HWND. But I didn't expect to find one either.


To get the rectangle reference to its parent. Look for something like:
Control.RectangleToScreen(), control.RectangleToClient().

Basically, convert the child window's rectangle to the screen, and then convert the screen to the parent's client.

[sammyh]

You are da man.

I was calling a dll function that wanted an HWND, but in C# you can only get an IntPtr.

It gave:
error C2664: cannot convert parameter 2 from 'System::IntPtr' to 'HWND'

but your snippet worked wonderfully.

Thank you very much

[WillemM]

Hwnd = 32 bit integer, so... in the class definition it would look like this.

Int32 hWnd;

or

int hWnd;

You can do the following with the IntPtr variable:

IntPtr.ToInt32();

So

hWnd = IntPtr.ToInt32();

see ?
Simple like it gets, and I think this works also !
(sorry can't test it at the moment)

[evschu]

I'm new to C, new to C++ and new to VC++.net, so you can imagine that i get frustrated, plus I'm learning DirectShow. anyway, this post helped alot.

What worked for me:

IntPtr handle;
handle = CppForm::get_Handle();
g_hwnd = (HWND)handle.ToInt32();


note: g_hwnd is a global variable