now I didn't have RegisterClassExW, how to import that ?

[Phil Lavoie]

In case you had not seen in the other thread:

On Sunday, 27 January 2013 at 14:06:00 UTC, rsk82 wrote:
> Ok, nevermind, found, it, it was so easy that it simply didn't 
> have to had an example:
>
>     struct WNDCLASSEXW {
>       UINT      cbSize;
>       UINT      style;
>       WNDPROC   lpfnWndProc;
>       int       cbClsExtra;
>       int       cbWndExtra;
>       HINSTANCE hInstance;
>       HICON     hIcon;
>       HCURSOR   hCursor;
>       HBRUSH    hbrBackground;
>       LPCWSTR   lpszMenuName;
>       LPCWSTR   lpszClassName;
>       HICON     hIconSm;
>     }

If you find yourself desiring other bindings of the win32 api and
don't want them to define them by hand, a project was started
some time ago by Stewart Gordon that contains an almost complete
set of bindings:
http://dsource.org/projects/bindings/wiki/WindowsApi

Set the import directory of your compiler appropriately and use
it like that:
import win32.winuser; //example, where you will probably find
wndclassexw

Additionnally, you should know that SOMETHINGA and SOMETHINGW
means A for ascii and W for wide chars (UCS-2, so every char
is two bytes instead of one). Normally, the api was intented to
be used without the extra letter at the end:

WNDCLASSEX wndclass; //No suffix: defaults to ascii.

When people compile with the preprocessor Unicode defined, then
all aliases are mapped to their W counterpart. What changes is
how you pass and receive strings.
Keep in mind they must be null terminated (as in C).

The microsoft bunch also defined another macro that would help
you make your code independant of the version used, it is called
TCHAR.
TCHAR * someString; //Will be char * without unicode or wchar
with.
someString = "My window class".toUTFz!( TCHAR * ); //This is how
I use the std library to convert my strings. Try to keep a handle
on strings that might be kept by the OS, to prevent them from
being garbage collected.

WNDCLASSEX wndclass;
...
wndclass.lpszClassName = someString;

Peace,
Phil

...

And because I forgot to mention, to mimic the preprocessor
directive, the bindings use a version conditional compilation.
Therefore, you use it like that:
rdmd -I/where/you/put/the/bindings -version=Unicode yourmodule.d

You can double check in the code, but IIRC, only the first letter
is capsed.