Format __int64 in CString - MFC

Format int64 string using CString.

Writes formatted data to a CStringT in the same way that sprintf formats data into a C-style character array. __int64 lMyPinCode = 691301; __int64 lFlat = 6; CString strMyPinCode; strMyPinCode.Format(_T("MyPinCode = %d, Flat = %d \n"),lMyPinCode,lFlat); _tprintf(strMyPinCode); Output MyPinCode = 691301, Flat = 0 Solution Use “long long” or Int64 format Specification . strMyPinCode.Format(_T("MyPinCode = %lld, Flat = %lld \n"),lMyPinCode,lFlat); _tprintf(strMyPinCode); strMyPinCode.Format(_T("MyPinCode = %I64d, Flat = %I64d \n"),lMyPinCode,lFlat); _tprintf(strMyPinCode); Output MyPinCode = 691301, Flat = 6 MyPinCode = 691301, Flat = 6