Delphi - Converting a char to pchar

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DLL Talk / Delphi - Converting a char to pchar

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MikeS

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Posted: 13th Jun 2005 06:31 Edited at: 13th Jun 2005 06:32

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//Returns the successing character in the alphabet.
function successor(letter:char):pchar;stdcall;
begin
   result := pchar(string(SUCC(letter)));
end;

Trying to get this little function to work with DBP. As I understand, DBP doesn't like Delphi's strings or char, so it has to be passed as a pchar. Might just be my lack of experience with Delphi, but this doesn't seem to be returning the correct letter in DBP.

+ Code Snippet

successor$ = Call Dll(1,"successor","y")

This code should return a z, but it returns an upside down question mark instead.

Any ideas of what's going on. Everything compiles fine, so I suspect something happens to my character when I convert the datatypes.

I tried to go straight from char to pchar, but that crashes DBP.

Thanks

A book? I hate book. Book is stupid.
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Location: 3 boats down from the candy

Posted: 15th Jun 2005 21:12

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function successor(letter: PChar): PChar; stdcall;
var temp: String;
begin
    temp := succ(letter^);
    result := StrAlloc(2);
    StrCopy(result, PChar(temp));
end;

Note that letter is passed as pchar as well.