Thread: double <--> unicode string

i need to convert double numbers to unicode string (wchar_t *) and back. how do i do that? all default conversion functions only support ansi.

-- double -> ansi string --
char *_gcvt( double value, int digits, char *buffer );
char *_fcvt( double value, int count, int *dec, int *sign );
char *_ecvt( double value, int count, int *dec, int *sign );

-- ansi string -> double --
double atof( const char *string );

using print-functions i cannot get more than 9 digits after: "%.9f".
in my case this is not enough so my current "solution" uses _gcvt, atof and these two:

Code:

void unicode_to_ansi( wchar_t * szInput, char * szOutput )
{
	UINT uLen = wcslen( szInput );
	while( *szInput != L'\0' )
	{
		*( szOutput++ ) = *( szInput++ ) & 255;
	}
	*szOutput = '\0';
}

void ansi_to_unicode( char * szInput, wchar_t * szOutput )
{
	UINT uLen = strlen( szInput );
	while( *szInput != '\0' )
	{
		*( szOutput++ ) = *( szInput++ );
	}
	*szOutput = L'\0';
}

>> using print-functions i cannot get more than 9 digits after: "%.9f". <<

That's weird. This seems to work for me.

Code:

	char buf[100];
	double dbl = 9.423445631463345345;

	sprintf(buf, "%.40f", dbl);
	printf("%s\n", buf);

Down converting to ansi seems to defeat the purpose of using unicode, but if you must, you should consider using the WideCharToMultibyte() and MultibyteToWideChar() functions.

Here is another option that gives more than 9 digits.

Code:

	BSTR bstr = NULL;
	double dbl = 9.423445631463345345;

	VarBstrFromR8(dbl, LOCALE_USER_DEFAULT, 0, &bstr);

	printf("%ls\n", bstr);

	SysFreeString(bstr);

the first one seems to works! - i thought it wouldn't. i remembered i once tested it with a two-digit number but maybe it was in php or so... it works and this seems to be the best solution to me. and i won't have to break unicode this way...

thanks for your qualified answers and for taking the time.

---

i needed this for a save-and-read-config-to-ini-file class that's part of a screensaver framework i am working on right now. i'll opst a thread here when i'm done...

if you like you can give me your real name, e-mail address and website url so i can add you to the thank-you-section!


thanx again // bass aka hartwork <[email protected]>