使用c++11标准库转换字符编码

#include <stdio.h>

#include <locale>

#include <codecvt>



const std::string ws2s( const std::wstring& src )

{

	std::locale sys_locale("");



	const wchar_t* data_from = src.c_str();

	const wchar_t* data_from_end = src.c_str() + src.size();

	const wchar_t* data_from_next = 0;



	int wchar_size = 4;

	char* data_to = new char[(src.size() + 1) * wchar_size];

	char* data_to_end = data_to + (src.size() + 1) * wchar_size;

	char* data_to_next = 0;



	memset( data_to, 0, (src.size() + 1) * wchar_size );



	typedef std::codecvt<wchar_t, char, mbstate_t> convert_facet;

	mbstate_t out_state = 0;

	auto result = std::use_facet<convert_facet>(sys_locale).out(

		out_state, data_from, data_from_end, data_from_next,

		data_to, data_to_end, data_to_next );

	if( result == convert_facet::ok )

	{

		std::string dst = data_to;

		delete[] data_to;

		return dst;

	}

	else

	{

		printf( "convert error!\n" );

		delete[] data_to;

		return std::string("");

	}

}



const std::wstring s2ws( const std::string& src )

{

	std::locale sys_locale("");

		

	const char* data_from = src.c_str();

	const char* data_from_end = src.c_str() + src.size();

	const char* data_from_next = 0;



	wchar_t* data_to = new wchar_t[src.size() + 1];

	wchar_t* data_to_end = data_to + src.size() + 1;

	wchar_t* data_to_next = 0;



	wmemset( data_to, 0, src.size() + 1 );



	typedef std::codecvt<wchar_t, char, mbstate_t> convert_facet;

	mbstate_t in_state = 0;

	auto result = std::use_facet<convert_facet>(sys_locale).in(

		in_state, data_from, data_from_end, data_from_next,

		data_to, data_to_end, data_to_next );

	if( result == convert_facet::ok )

	{

		std::wstring dst = data_to;

		delete[] data_to;

		return dst;

	}

	else

	{

		printf( "convert error!\n" );

		delete[] data_to;

		return std::wstring(L"");

	}

}



const std::string ws2utf8( const std::wstring& src )

{

	std::wstring_convert<std::codecvt_utf8<wchar_t>> conv;

	return conv.to_bytes( src );

}



const std::wstring utf8_2_ws( const std::string& src )

{

	std::wstring_convert<std::codecvt_utf8<wchar_t> > conv;

	return conv.from_bytes( src );

}

遇到0X2C 0XA0的UTF8字符编码进行特殊处理，转换成普通空格。