[fpc-devel] twide3.pp on windows

[Yury Sidorov]

From: "Daniël Mantione" <daniel.mantione at freepascal.org>
> Op Mon, 16 Jul 2007, schreef Yury Sidorov:
>
> > The code page (locale) is set in Control Panel for whole user 
> > session (or
> > whole system).
> > It is not possible to set utf8 as locale.
>
> I know. How do you set it to a specific locale for the current
> application?

widestring to ansistring conversion is performed using 
WideCharToMultiByte. Currently it is done using ANSI code page 
specified in Control Panel.
There is no per application code page setting in Windows.

> > We can create flag in System unit which control how 
> > widestring<->ansistring
> > should be performed to enable utf8 on Windows.
>
> No, you cannot (at least not with full functionality), since 
> uppercasing
> and compare operations on UTF-8 ansistrings you need a Unicode 
> library,
> which Windows does only provide in UTF-16 flavour.

WideCharToMultiByte can convert from widestring to utf8 if 
corresponding flag is specified. This flag is available in Windows 
98/Me, Windows NT 4.0 and later.
MultiByteToWideChar do reverse conversion.

This functions already used in System unit for Windows.

Yury.