Convenient easy-to-use and efficient helper functions to convert between Unicode UTF-16 and UTF-8 using ATL CString

This project contains a header-only C++ file that implements a couple of functions to simply, efficiently, and conveniently convert Unicode text between UTF-16 and UTF-8, using ATL CString classes and direct Win32 API calls.

CStringW is used to store UTF-16-encoded text. CStringA is used to store UTF-8-encoded text.

The exported functions are:

    // Convert from UTF-16 to UTF-8
    CStringA ToUtf8(CStringW const& utf16)
    
    // Convert from UTF-8 to UTF-16
    CStringW ToUtf16(CStringA const& utf8)

These functions live under the UnicodeConvAtl namespace.

This code compiles cleanly at warning level 4 (/W4) on both 32-bit and 64-bit builds.

Just #include "UnicodeConvAtl.h" in your projects, and enjoy!

This code has been written and compiled with Visual Studio 2019. If you want to back-port it to older C++ compilers (like VS 2008) that don't implement C++11+ features, you can simply:

• replace all the occurrences of nullptr with NULL
• replace all the occurrences of constexpr with static const