unit CrtLib;
interface

 function Dbl2Str(lf:Double):string;
 function Dbl2Sta(lf:Double):AnsiString;
 function Dbl2StrN(Lf:Double;pr:Cardinal = 3):string;
 function Dbl2StaN(lf:Double;pr:Cardinal = 3):AnsiString;
 function Str2Dbl(const wStr :String):Double;     overload;
 function Str2Dbl(const aStr :AnsiString):Double; overload;

 function sprintf (S: PAnsiChar; const Format: PAnsiChar): Integer; cdecl; varargs;
 function swprintf(S: PChar;     const Format: PChar)    : Integer; cdecl; varargs;
 function strtod(s :PAnsiChar ; endptr:PPAnsiChar): double; cdecl;
 function wcstod(s :PChar ; endptr:PPChar): double; cdecl;

implementation

const
 msvcrt = 'msvcrt.dll';

 function sprintf (S: PAnsiChar; const Format: PAnsiChar): Integer; cdecl; varargs; external msvcrt;
 function swprintf(S: PChar;     const Format: PChar)    : Integer; cdecl; varargs; external msvcrt;
 function strtod(s :PAnsiChar ; endptr:PPAnsiChar): Double; cdecl; external msvcrt;
 function wcstod(s :PChar ; endptr:PPChar): Double; cdecl; external msvcrt;

function Dbl2Str(lf:Double):string;
const cFmt = UnicodeString('%lg');
var   Buff:array [0..1023] of Char;
begin
 SetString(Result,Buff,swprintf(Buff, cFmt, Lf));
end;

function Dbl2StrN(Lf:Double;pr:Cardinal):string;
const
 cFmt = UnicodeString('%.*lf');
var
 Buff:array [0..1023] of Char;
begin
 SetString(Result,Buff,swprintf(Buff, cFmt, pr, Lf));
end;

function Dbl2Sta(Lf:Double):AnsiString;
const
 cFmt = AnsiString('%lg');
var
 Buff:array [0..1023] of AnsiChar;
begin
 SetString(Result,Buff,sprintf(Buff, cFmt, Lf));
end;

function Dbl2StaN(Lf:Double;pr:Cardinal):AnsiString;
const cFmt = AnsiString('%.*lf');
var   Buff:array [0..1023] of AnsiChar;
begin
 SetString(Result,Buff,sprintf(Buff, cFmt, pr, Lf));
end;

function Str2Dbl(const wStr :String):Double;
var
 eP : PChar;
begin
 Result := wcstod(PChar(wStr),@eP);
end;

function Str2Dbl(const aStr :AnsiString):Double;
var
 eP : PAnsiChar;
begin
 Result := strtod(PAnsiChar(aStr),@eP);
end;

end.