Can't get DwmGetWindowAttribute to work

[Slion]

I tried a bunch of stuff including the following all I get is null reference exception thrown by DwmGetWindowAttribute.

        PInvoke.RECT rect = new PInvoke.RECT();
        int size = Marshal.SizeOf(typeof(PInvoke.RECT));
        IntPtr rectPtr = Marshal.AllocHGlobal(size);
        PInvoke.DwmApi.DwmGetWindowAttribute(hwnd, DwmApi.DWMWINDOWATTRIBUTE.DWMWA_EXTENDED_FRAME_BOUNDS,out rectPtr,size);
        Marshal.PtrToStructure(rectPtr, rect);
        Marshal.FreeHGlobal(rectPtr);

It's a lot faster to get it working using that solution: https://stackoverflow.com/a/58675103/3969362

[AArnott]

It looks like we incorrectly use out and a pointer type, which turns into a double-pointer.

[AArnott]

Thanks for reporting, @Slion

[Slion]

Congrats on the quick turn around. @AArnott Any chance of having an overload taking RECT as parameter much like on that stackoverflow post linked above?

[AArnott]

No. Our convention is to use the same types used in the native signature. But it shouldn't be hard for you to use RECT. Much easier than your original code nsippet.

Something like this:

unsafe void Foo()
{
        PInvoke.RECT rect = new PInvoke.RECT();
        PInvoke.DwmApi.DwmGetWindowAttribute(hwnd, DwmApi.DWMWINDOWATTRIBUTE.DWMWA_EXTENDED_FRAME_BOUNDS, &rect, sizeof(rect));
}

Don't worry about the 'unsafe' code. It doesn't mean your caller has to be unsafe. And honestly, this way you're not responsible for allocating, freeing, and copying native memory that could leak. C# pointer code is much easier than all this IntPtr nonsense that was invented to support poor VB.

[Slion]

@AArnott Thanks for that insight. When will that fix make it into a release?

[AArnott]

It looks like it's been quite a while, with quite a bit of work, since our last release. I'll go ahead and release to nuget.org today.