My_String

My_String.h

#pragma once
#include <iostream>
#include <string> 
#include <stdlib.h> 
std::wstring string2wstring(std::string str);
std::string wstring2string(std::wstring wstr);
std::string& replace_all(std::string& str, const std::string&  old_value, const std::string& new_value);
std::string& replace_all_distinct(std::string& str, const  std::string& old_value, const std::string& new_value);
#ifdef _WIN32
#include <windows.h>

std::string GbkToUtf8(const char *src_str);
std::string Utf8ToGbk(const char *src_str);
#else
#include <iconv.h>
int GbkToUtf8(char *str_str, size_t src_len, char *dst_str, size_t dst_len);
int Utf8ToGbk(char *src_str, size_t src_len, char *dst_str, size_t dst_len);
#endif
 

My_String.cpp

#include "My_String.h"
std::wstring string2wstring(std::string str)
{
	std::wstring result;
	int len = MultiByteToWideChar(CP_ACP, 0, str.c_str(), str.size(), NULL, 0);
	wchar_t* buffer = new wchar_t[len + 1];
	MultiByteToWideChar(CP_ACP, 0, str.c_str(), str.size(), buffer, len);
	buffer[len] = '\0';
	result.append(buffer);
	delete[] buffer;
	return result;
}

std::string wstring2string(std::wstring wstr)
{
	std::string result;
	int len = WideCharToMultiByte(CP_ACP, 0, wstr.c_str(), wstr.size(), NULL, 0, NULL, NULL);
	char* buffer = new char[len + 1];
	WideCharToMultiByte(CP_ACP, 0, wstr.c_str(), wstr.size(), buffer, len, NULL, NULL);
	buffer[len] = '\0';
	result.append(buffer);
	delete[] buffer;
	return result;
}
std::string& replace_all(std::string& str, const std::string&  old_value, const std::string& new_value)
{
	while (true) {
		std::string::size_type pos(0);
		if ((pos = str.find(old_value)) != std::string::npos)
			str.replace(pos, old_value.length(), new_value);
		else   break;
	}
	return   str;
}
 
std::string& replace_all_distinct(std::string& str, const  std::string& old_value, const std::string& new_value)
{
	for (std::string::size_type pos(0); pos != std::string::npos; pos += new_value.length()) {
		if ((pos = str.find(old_value, pos)) != std::string::npos)
			str.replace(pos, old_value.length(), new_value);
		else  break;
	}
	return str;
}
#ifdef _WIN32
#include <windows.h>

std::string GbkToUtf8(const char *src_str)
{
	int len = MultiByteToWideChar(CP_ACP, 0, src_str, -1, NULL, 0);
	wchar_t* wstr = new wchar_t[len + 1];
	memset(wstr, 0, len + 1);
	MultiByteToWideChar(CP_ACP, 0, src_str, -1, wstr, len);
	len = WideCharToMultiByte(CP_UTF8, 0, wstr, -1, NULL, 0, NULL, NULL);
	char* str = new char[len + 1];
	memset(str, 0, len + 1);
	WideCharToMultiByte(CP_UTF8, 0, wstr, -1, str, len, NULL, NULL);
	std::string strTemp = str;
	if (wstr) delete[] wstr;
	if (str) delete[] str;
	return strTemp;
}

std::string Utf8ToGbk(const char *src_str)
{
	int len = MultiByteToWideChar(CP_UTF8, 0, src_str, -1, NULL, 0);
	wchar_t* wszGBK = new wchar_t[len + 1];
	memset(wszGBK, 0, len * 2 + 2);
	MultiByteToWideChar(CP_UTF8, 0, src_str, -1, wszGBK, len);
	len = WideCharToMultiByte(CP_ACP, 0, wszGBK, -1, NULL, 0, NULL, NULL);
	char* szGBK = new char[len + 1];
	memset(szGBK, 0, len + 1);
	WideCharToMultiByte(CP_ACP, 0, wszGBK, -1, szGBK, len, NULL, NULL);
	std::string strTemp(szGBK);
	if (wszGBK) delete[] wszGBK;
	if (szGBK) delete[] szGBK;
	return strTemp;
}
#else
#include <iconv.h>

int GbkToUtf8(char *str_str, size_t src_len, char *dst_str, size_t dst_len)
{
	iconv_t cd;
	char **pin = &str_str;
	char **pout = &dst_str;

	cd = iconv_open("utf8", "gbk");
	if (cd == 0)
		return -1;
	memset(dst_str, 0, dst_len);
	if (iconv(cd, pin, &src_len, pout, &dst_len) == -1)
		return -1;
	iconv_close(cd);
	*pout = '\0';

	return 0;
}

int Utf8ToGbk(char *src_str, size_t src_len, char *dst_str, size_t dst_len)
{
	iconv_t cd;
	char **pin = &src_str;
	char **pout = &dst_str;

	cd = iconv_open("gbk", "utf8");
	if (cd == 0)
		return -1;
	memset(dst_str, 0, dst_len);
	if (iconv(cd, pin, &src_len, pout, &dst_len) == -1)
		return -1;
	iconv_close(cd);
	*pout = '\0';

	return 0;
}


#endif