[Lazarus] UTF8String and UTF8Delete

[Bart]

On 12/11/15, Sven Barth <pascaldragon at googlemail.com> wrote:

> Not necessarily. You can use SetCodePage() to change the code page of
> the string without triggering a codepage conversion by using the third
> parameter which is a Boolean that tells the function to either do a
> conversion (True; default) or not (False). You'd then need to declare
> the UTF8* routines as RawByteString and explicitly handle the type
> conversion.

That's not really an option since it will break every single program
using those functions.

AFAIK the Utf8* functions assume their input is UTF8 encoded (they do
not check), so something like this should work?

{$ifndef NO_CP_RTL}
procedure Utf8Delete(var S: Utf8String; StartCharIndex, CharCount:
PtrInt); overload;
var
  Temp: String;
begin
  SetLength(Temp, Length(S));
  Move(S[1], Temp[1], Length(S));
  //nex step might not be needed?
  SetCodePage(RawBytestring(Temp), CP_UTF8, False);
  UTF8Delete(Temp, StartCharIndex, CharCount);
  SetLength(S, Length(Temp));
  Move(Temp[1], S[1], Length(Temp));
end;
{$endif}

Anyhow, as stated before, there should be noneed to use the type
Utf8String in Lazarus programs.

Bart