While Windows supports dozens or even hundreds of languages, its localization APIs require quite a bit of getting used to. Below is how I solved some common problems related to formatting and parsing a number for a specific locale.

Formatting a Number for a Locale

The function GetNumberFormat() formats a number for a particular locale. Its simplest usage looks something like:

#define ARRAYSIZE(x) ( sizeof(x) / sizeof(x[0]) )

TCHAR buf[80];
int ret = GetNumberFormat
    (
    LOCALE_USER_DEFAULT, // locale
    0,                   // dwFlags
    TEXT("1234567.89"),  // lpValue
    NULL,                // lpFormat
    buf,                 // lpNumberStr
    ARRAYSIZE(buf)       // cchNumber
    );
ASSERT(ret != 0);

buf now contains the number 1234567.89 formatted for the user’s default locale. For example, for the English-United States locale, buf will contain “1,234,567.89”; for German-Germany, “1.234.567,89”; for Hindi, “12,34,567.89”.