（转） C++ Utf8字符转换Gb312编码，解决TinyXml中文乱码

原文地址：http://cjmxp007.blog.163.com/blog/static/35473837201061541933667/

  1 #ifndef TRANSFORM
  2 #define TRANSFORM
  3 #include <map>
  4 using namespace std;
  5 // 是否启用map转换，建议启用
  6 // 使用map转换的话，同一个常量字符串不会做两次转换
  7 #define TEST_TYPE_MAP
  8 
  9 typedef map<const char*, const char*> strmap;
 10 
 11 class CUtf8String
 12 {
 13     public:
 14         inline CUtf8String(const char* gb2312)
 15         {
 16             m_bIsConst = true;
 17 #ifdef TEST_TYPE_MAP
 18             if (m[gb2312])
 19             {
 20                 m_utf8 = m[gb2312];
 21                 return ;
 22             }
 23 #endif
 24             int buffLen = 0;
 25             WCHAR wbuff[5120];
 26             MultiByteToWideChar(CP_ACP, 0, gb2312, -1, wbuff, 5120);
 27             buffLen = WideCharToMultiByte(CP_UTF8, 0, wbuff, -1, NULL, 0, 0, 0);
 28             m_utf8 = new char[buffLen+1];
 29             WideCharToMultiByte(CP_UTF8, 0, wbuff, -1, (LPSTR)m_utf8, buffLen, 0, 0);
 30 #ifdef TEST_TYPE_MAP
 31             m[gb2312] = m_utf8;
 32 #endif
 33         }
 34 
 35         inline CUtf8String(char* gb2312)
 36         {
 37             m_bIsConst = false;
 38             int buffLen = 0;
 39             WCHAR wbuff[5120];
 40             MultiByteToWideChar(CP_ACP, 0, gb2312, -1, wbuff, 5120);
 41             buffLen = WideCharToMultiByte(CP_UTF8, 0, wbuff, -1, NULL, 0, 0, 0);
 42             m_utf8 = new char[buffLen+1];
 43             WideCharToMultiByte(CP_UTF8, 0, wbuff, -1, (LPSTR)m_utf8, buffLen, 0, 0);
 44         }
 45 
 46         inline ~CUtf8String()
 47             {
 48 #ifndef TEST_TYPE_MAP
 49             if (m_utf8)
 50             {
 51                 delete m_utf8;
 52                 m_utf8 = 0;
 53             }
 54 #else
 55             if (!m_bIsConst)
 56                 {
 57                 if (m_utf8)
 58                     {
 59                     delete m_utf8;
 60                     m_utf8 = 0;
 61                     }
 62                 }
 63 #endif
 64             }
 65 
 66         inline operator char*()
 67             {
 68             return (char*)m_utf8;
 69             }
 70     private:
 71         const char* m_utf8;
 72         bool m_bIsConst;
 73 #ifdef TEST_TYPE_MAP
 74         static strmap m;
 75 #endif
 76 };
 77 
 78 class CGb2312String
 79     {
 80     public:
 81         inline CGb2312String(const char* utf8)
 82             {
 83 #ifdef TEST_TYPE_MAP
 84             if (m[utf8])
 85             {
 86                 m_gb2312 = 0;
 87                 m_gb2312 = m[utf8];
 88             }
 89 #endif
 90             int buffLen = 0;
 91             WCHAR wbuff[5120];
 92             MultiByteToWideChar(CP_UTF8, 0, utf8, -1, wbuff, 5120);
 93             buffLen = WideCharToMultiByte(CP_ACP, 0, wbuff, -1, NULL, 0, 0, 0);
 94             m_gb2312 = new char[buffLen+1];
 95             WideCharToMultiByte(CP_ACP, 0, wbuff, -1, (LPSTR)m_gb2312, buffLen, 0, 0);
 96 #ifdef TEST_TYPE_MAP
 97             m[utf8] = m_gb2312;
 98 #endif
 99         }
100 
101         inline CGb2312String(char* utf8)
102         {
103 #ifdef TEST_TYPE_MAP
104             if (m[utf8])
105             {
106                 m_gb2312 = 0;
107                 m_gb2312 = m[utf8];
108             }
109 #endif
110             int buffLen = 0;
111             WCHAR wbuff[5120];
112             MultiByteToWideChar(CP_UTF8, 0, utf8, -1, wbuff, 5120);
113             buffLen = WideCharToMultiByte(CP_ACP, 0, wbuff, -1, NULL, 0, 0, 0);
114             m_gb2312 = new char[buffLen+1];
115             WideCharToMultiByte(CP_ACP, 0, wbuff, -1, (LPSTR)m_gb2312, buffLen, 0, 0);
116 #ifdef TEST_TYPE_MAP
117             m[utf8] = m_gb2312;
118 #endif
119         }
120 
121         inline ~CGb2312String()
122         {
123 #ifndef TEST_TYPE_MAP
124             if (m_gb2312)
125                 {
126                 delete m_gb2312;
127                 m_gb2312 = 0;
128                 }
129 #endif
130         }
131 
132         inline operator char*()
133         {
134             return (char*)m_gb2312;
135         }
136     private:
137         const char* m_gb2312;
138 #ifdef TEST_TYPE_MAP
139         static strmap m;
140 #endif
141 };
142 
143 #ifdef TEST_TYPE_MAP
144 strmap CUtf8String::m;
145 strmap CGb2312String::m;
146 #endif
147 #endif
148 
149 
150 //===================无聊的分割线==========================
151 
152 #define U   (CUtf8String)
153 
154 #define W   (CGb2312String)
155 
156 // 使用方法
157 int main(int argc, char* argv[])
158 {
159     // 打印出乱码即为UTF8的编码，方便吧。C++还是确实很强悍的
160     printf("%s", U"你好中国!");
161 }