strCoder.h

//strCoder.h
#pragma once

#include "Winsock2.h"
#include "windows.h"

#include <iostream>
#include <fstream>
#include <sstream>

#include <locale>
#include <codecvt>
#include <string>


void string2num(std::string str, double& num) {
	std::stringstream ss; ss << str; ss >> num;
}

void string2num(std::string str, int& num) {
	std::stringstream ss; ss << str; ss >> num;
}

std::string StringToUTF8(const std::string& gbkData)
{
	const char* GBK_LOCALE_NAME = "CHS";
	//GBKÔÚwindowsϵÄlocale name(.936, CHS ), linuxϵÄlocaleÃû¿ÉÄÜÊÇ"zh_CN.GBK"

	std::wstring_convert<std::codecvt<wchar_t, char, mbstate_t>>
		conv(new std::codecvt<wchar_t, char, mbstate_t>(GBK_LOCALE_NAME));
	std::wstring wString = conv.from_bytes(gbkData);    // string => wstring

	std::wstring_convert<std::codecvt_utf8<wchar_t>> convert;
	std::string utf8str = convert.to_bytes(wString);     // wstring => utf-8

	return utf8str;
}


std::string UTF8ToString(const std::string& utf8Data)
{
	std::wstring_convert<std::codecvt_utf8<wchar_t>> conv;
	std::wstring wString = conv.from_bytes(utf8Data);    // utf-8 => wstring

	std::wstring_convert<std::codecvt< wchar_t, char, std::mbstate_t>>
		convert(new std::codecvt< wchar_t, char, std::mbstate_t>("CHS"));
	std::string str = convert.to_bytes(wString);     // wstring => string

	return str;
}


std::string UnicodeToUTF8(const std::wstring& wstr)
{
	std::string ret;
	try {
		std::wstring_convert< std::codecvt_utf8<wchar_t> > wcv;
		ret = wcv.to_bytes(wstr);
	}
	catch (const std::exception& e) {
		std::cerr << e.what() << std::endl;
	}
	return ret;
}


std::wstring UTF8ToUnicode(const std::string& str)
{
	std::wstring ret;
	try {
		std::wstring_convert< std::codecvt_utf8<wchar_t> > wcv;
		ret = wcv.from_bytes(str);
	}
	catch (const std::exception& e) {
		std::cerr << e.what() << std::endl;
	}
	return ret;
}


std::string UnicodeToANSI(const std::wstring& wstr)
{
	std::string ret;
	std::mbstate_t state = {};
	const wchar_t* src = wstr.data();
	size_t len = std::wcsrtombs(nullptr, &src, 0, &state);
	if (static_cast<size_t>(-1) != len) {
		std::unique_ptr< char[] > buff(new char[len + 1]);
		len = std::wcsrtombs(buff.get(), &src, len, &state);
		if (static_cast<size_t>(-1) != len) {
			ret.assign(buff.get(), len);
		}
	}
	return ret;
}


std::wstring ANSIToUnicode(const std::string& str)
{
	std::wstring ret;
	std::mbstate_t state = {};
	const char* src = str.data();
	size_t len = std::mbsrtowcs(nullptr, &src, 0, &state);
	if (static_cast<size_t>(-1) != len) {
		std::unique_ptr< wchar_t[] > buff(new wchar_t[len + 1]);
		len = std::mbsrtowcs(buff.get(), &src, len, &state);
		if (static_cast<size_t>(-1) != len) {
			ret.assign(buff.get(), len);
		}
	}
	return ret;
}


std::string UTF8ToANSI(const std::string& str)
{
	return UnicodeToANSI(UTF8ToUnicode(str));
}


std::string ANSIToUTF8(const std::string& str)
{
	return UnicodeToUTF8(ANSIToUnicode(str));
}

unsigned char ToHex(unsigned char x)
{
	return  x > 9 ? x + 55 : x + 48;
}

unsigned char FromHex(unsigned char x)
{
	unsigned char y;
	if (x >= 'A' && x <= 'Z') y = x - 'A' + 10;
	else if (x >= 'a' && x <= 'z') y = x - 'a' + 10;
	else if (x >= '0' && x <= '9') y = x - '0';
	else assert(0);
	return y;
}

std::string UrlEncode(const std::string& str)
{
	std::string strTemp = "";
	size_t length = str.length();
	for (size_t i = 0; i < length; i++)
	{
		if (isalnum((unsigned char)str[i]) ||
			(str[i] == '-') ||
			(str[i] == '_') ||
			(str[i] == '.') ||
			(str[i] == '~'))
			strTemp += str[i];
		else if (str[i] == ' ')
			strTemp += "+";
		else
		{
			strTemp += '%';
			strTemp += ToHex((unsigned char)str[i] >> 4);
			strTemp += ToHex((unsigned char)str[i] % 16);
		}
	}
	return strTemp;
}

std::string UrlDecode(const std::string& str)
{
	std::string strTemp = "";
	size_t length = str.length();
	for (size_t i = 0; i < length; i++)
	{
		if (str[i] == '+') strTemp += ' ';
		else if (str[i] == '%')
		{
			assert(i + 2 < length);
			unsigned char high = FromHex((unsigned char)str[++i]);
			unsigned char low = FromHex((unsigned char)str[++i]);
			strTemp += high * 16 + low;
		}
		else strTemp += str[i];
	}
	return strTemp;
}