How to convert UTF-8 std::string to UTF-16 std::wstring?

Question

If I have a UTF-8 std::string how do I convert it to a UTF-16 std::wstring? Actually, I want to compare two Persian words.

Answer 1

This page also seems useful: http://www.codeproject.com/KB/string/UtfConverter.aspx

In the comment section of that page, there are also some interesting suggestions for this task like:

// Get en ASCII std::string from anywhere
std::string sLogLevelA = "Hello ASCII-world!";

std::wstringstream ws;
ws << sLogLevelA.c_str();
std::wstring sLogLevel = ws.str();

Or

// To std::string:
str.assign(ws.begin(), ws.end());
// To std::wstring
ws.assign(str.begin(), str.end());

Though I'm not sure the validity of these approaches...