Re: Converting WideChar/WideString to AnsiChar/AnsiString

On 29 Mai, 14:41, Rob Kennedy <m...@xxxxxxxxxxx> wrote:
ckoegl wrote:
I cannot find anything definitive in the Delphi docs and in the
relevant newsgroups that answers this simple question:

What is the exact definition of the WideChar to AnsiChar conversion
(and in extension of the WideString to AnsiString conversion)?

I suppose that for all WideChar values that are valid AnsiChar values
(i.e. the ones with Ord-values of 0 to 255) are preserved in the
conversion, but what about the rest?

They're truncated, I think. Or it's a range-check error.

Converting a WideString to an AnsiString involves converting the
WideString to the current system code page, but I'm pretty sure that
effort is *not* used for converting WideChar to AnsiChar.

And if that's the case, then the conversion is nonsense. Don't do it.

--
Rob

Ok, in my case I simply cannot dodge the problem: I have (for whatever
reasons) text
data given as WideString and I need to call given procedures/functions
that only accept
String (which in my case means AnsiString). It is entirely acceptable
that some data
ist lost during the WideString to String conversion, but: (1) All
character information that
can be transferred should be transferred, and (2) I need to know quite
exactly what happens
in case unconvertible character data is encountered.

Well, I guess I could simply try out what happens, but I thought that
maybe you
folks already have deeper experience of what pitfalls may lie ahead of
me ...

One valuable information I already got is that the string conversion
is not simply a sequence
of single character conversions.

Thanks,

Christoph
.

Relevant Pages

  • Re: IDE products roadmap updated
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    (borland.public.delphi.non-technical)
  • Re: Converting WideChar/WideString to AnsiChar/AnsiString
    ... What is the exact definition of the WideChar to AnsiChar conversion ... I suppose that for all WideChar values that are valid AnsiChar values ... Converting a WideString to an AnsiString involves converting the WideString to the current system code page, but I'm pretty sure that effort is *not* used for converting WideChar to AnsiChar. ...
    (alt.comp.lang.borland-delphi)
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