incompatible types, String and PChar

hi,

When trying to find the Windows dir I use this,

Var
WinDirLen: Integer;
WinDir: PChar;
dir : string;
Begin
GetMem(WinDir, 255);
WinDirLen := GetSystemDirectory(WinDir,255);
dir := Windir;
FreeMem(WinDir);
end;

And I have this in my FormCreate;

Image1.Picture.Bitmap.Handle:= NViewLibLoad('c:\Program Files\Empire\800x600.jpg',false);

if I use this

Image1.Picture.Bitmap.Handle:= NViewLibLoad(dir + '800x600.jpg',false);
I get incompatible types String and PChar;

Please show me how it will work.

this is in the var that follows before implementation.
function NViewLibLoad(FileName : PChar; ShowProgress: BooLean):hbitmap; Stdcall; external 'NViewLib.dll';
hellfire052497Asked:
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mirek071497Commented:
I think so you need to know how the conversion between strings can be done.

in many ways.

Image1.Picture.Bitmap.Handle:= NViewLibLoad( PChar( string(dir) + '800x600.jpg' ),false);

when s is type PChar then String(s) give you long string.
when s is Long String then PChar(s) give you type PChar.

so in your problem string(dir) give you long string
PChar(      string(dir)+'800x600.jpg'   ) give you PChar.
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mirek071497Commented:
Hi

sorry i just see so dir is string no pchar. Then you can use use this without string(dir) :

Image1.Picture.Bitmap.Handle:= NViewLibLoad( PChar( dir + '800x600.jpg' ),false);

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