C++ GB2312与UTF-8之间的相互转换（Windows）

痛定思痛。 2021-12-09 05:21 387阅读 0赞

#include <windows.h>
    #include <sstream>
    #include <string>
    
    // UTF-8转GB2312
    std::string UTF8ToGBEx(const char *utf8)
    {
    	if (!utf8 || strlen(utf8) < 1)
    		return "";
    
    	std::stringstream ss;
    	int len = MultiByteToWideChar(CP_UTF8, 0, utf8, -1, NULL, 0);
    	wchar_t *wstr = new wchar_t[len + 1];
    	memset(wstr, 0, len + 1);
    	MultiByteToWideChar(CP_UTF8, 0, utf8, -1, wstr, len);
    	len = WideCharToMultiByte(CP_ACP, 0, wstr, -1, NULL, 0, NULL, NULL);
    	char *str = new char[len + 1];
    	memset(str, 0, len + 1);
    	WideCharToMultiByte(CP_ACP, 0, wstr, -1, str, len, NULL, NULL);
    	ss << str;
    	delete []wstr;
    	delete []str;
    	return ss.str();
    }
    
    // GB2312转UTF-8
    std::string GBToUTF8Ex(const char *gb2312)
    {
    	if (!gb2312 || strlen(gb2312) < 1)
    		return "";
    
    	std::stringstream ss;
    	int len = MultiByteToWideChar(CP_ACP, 0, gb2312, -1, NULL, 0);
    	wchar_t *wstr = new wchar_t[len + 1];
    	memset(wstr, 0, len + 1);
    	MultiByteToWideChar(CP_ACP, 0, gb2312, -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);
    	ss << str;
    	delete []wstr;
    	delete []str;
    	return ss.str();
    }
    
    std::string UTF8ToGBEx(const std::string &utf8)
    {
    	if (utf8.empty())
    		return "";
    
    	std::stringstream ss;
    	int len = MultiByteToWideChar(CP_UTF8, 0, utf8.c_str(), -1, NULL, 0);
    	wchar_t *wstr = new wchar_t[len + 1];
    	memset(wstr, 0, len + 1);
    	MultiByteToWideChar(CP_UTF8, 0, utf8.c_str(), -1, wstr, len);
    	len = WideCharToMultiByte(CP_ACP, 0, wstr, -1, NULL, 0, NULL, NULL);
    	char *str = new char[len + 1];
    	memset(str, 0, len + 1);
    	WideCharToMultiByte(CP_ACP, 0, wstr, -1, str, len, NULL, NULL);
    	ss << str;
    	delete []wstr;
    	delete []str;
    	return ss.str();
    }
    
    std::string GBToUTF8Ex(const std::string &gb2312)
    {
    	if (gb2312.empty())
    		return "";
    
    	std::stringstream ss;
    	int len = MultiByteToWideChar(CP_ACP, 0, gb2312.c_str(), -1, NULL, 0);
    	wchar_t *wstr = new wchar_t[len + 1];
    	memset(wstr, 0, len + 1);
    	MultiByteToWideChar(CP_ACP, 0, gb2312.c_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);
    	ss << str;
    	delete []wstr;
    	delete []str;
    	return ss.str();
    }
    
    // UTF-8转GB2312, 需用户手动delete
    char *UTF8ToGB(const char *utf8)
    {
    	if (!utf8 || strlen(utf8) < 1)
    		return 0;
    
    	int len = MultiByteToWideChar(CP_UTF8, 0, utf8, -1, NULL, 0);
    	wchar_t *wstr = new wchar_t[len + 1];
    	memset(wstr, 0, len + 1);
    	MultiByteToWideChar(CP_UTF8, 0, utf8, -1, wstr, len);
    	len = WideCharToMultiByte(CP_ACP, 0, wstr, -1, NULL, 0, NULL, NULL);
    	char* str = new char[len + 1];
    	memset(str, 0, len + 1);
    	WideCharToMultiByte(CP_ACP, 0, wstr, -1, str, len, NULL, NULL);
    	delete []wstr;
    	return str;
    }
    
    // GB2312转UTF-8，需用户手动delete
    char *GBToUTF8(const char *gb2312)
    {
    	if (!gb2312 || strlen(gb2312) < 1)
    		return 0;
    
    	int len = MultiByteToWideChar(CP_ACP, 0, gb2312, -1, NULL, 0);
    	wchar_t *wstr = new wchar_t[len + 1];
    	memset(wstr, 0, len + 1);
    	MultiByteToWideChar(CP_ACP, 0, gb2312, -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);
    	delete []wstr;
    	return str;
    }