宽字符和窄字符之间的转换，以及对中文的处理问题总汇

直接代码：

注：编译环境VS2010 SP1

  1 /*实现宽字节和窄字符转换以及中文文件的输入输出*/

  2 

  3 #include <iostream>

  4 #include <string>

  5 #include <fstream>

  6 #include <locale>

  7 #include <codecvt>

  8 #include <windows.h>

  9 #include <tchar.h>

 10 using namespace std;

 11 

 12 //-----------------------------------------------------------------------------

 13 //转换宽窄字符串时可以成功，并且支持中文转换

 14 const std::wstring s2ws(const std::string& s)

 15 {

 16     std::locale old_loc = std::locale::global(std::locale(""));

 17     const char* src_str = s.c_str();

 18     const size_t buffer_size = s.size() + 1;

 19     wchar_t* dst_wstr = new wchar_t[buffer_size];

 20     wmemset(dst_wstr, 0, buffer_size);

 21     mbstowcs(dst_wstr, src_str, buffer_size);

 22     std::wstring result = dst_wstr;

 23     delete []dst_wstr;

 24     std::locale::global(old_loc);

 25     return result;

 26 }

 27 const std::string ws2s(const std::wstring& ws)

 28 {

 29     std::locale old_loc = std::locale::global(std::locale(""));

 30     const wchar_t* src_wstr = ws.c_str();

 31     size_t buffer_size = ws.size() * 4 + 1;

 32     char* dst_str = new char[buffer_size];

 33     memset(dst_str, 0, buffer_size);

 34     wcstombs(dst_str ,src_wstr, buffer_size);

 35     std::string result = dst_str;

 36     delete []dst_str;

 37     std::locale::global(old_loc);

 38     return result;

 39 }

 40 

 41 //-----------------------------------------------------------------------------

 42 //转换宽窄字符串时可以成功，并且支持中文转换

 43 std::string WChar2Ansi(LPCWSTR pwszSrc)

 44 {

 45     int nLen = WideCharToMultiByte(CP_ACP, 0, pwszSrc, -1, NULL, 0, NULL, NULL);

 46 

 47     if (nLen<= 0) return std::string("");

 48 

 49     char* pszDst = new char[nLen];

 50     if (NULL == pszDst) return std::string("");

 51     ZeroMemory(pszDst, nLen);

 52 

 53     WideCharToMultiByte(CP_ACP, 0, pwszSrc, -1, pszDst, nLen, NULL, NULL);

 54     pszDst[nLen -1] = 0;

 55 

 56     std::string strTemp(pszDst);

 57     delete [] pszDst;

 58 

 59     return strTemp;

 60 }

 61 std::wstring Ansi2WChar(LPCSTR pszSrc, int nLen)

 62 

 63 {

 64     int nSize = MultiByteToWideChar(CP_ACP, 0, (LPCSTR)pszSrc, nLen, 0, 0);

 65     if(nSize <= 0) return NULL;

 66 

 67     WCHAR *pwszDst = new WCHAR[nSize+1];

 68     if( NULL == pwszDst) return NULL;

 69     ZeroMemory(pwszDst, nSize);

 70 

 71     MultiByteToWideChar(CP_ACP, 0, pszSrc, nLen, pwszDst, nSize);

 72     pwszDst[nSize] = 0;

 73 

 74     if( pwszDst[0] == 0xFEFF) // skip Oxfeff

 75         for(int i = 0; i < nSize; i ++)

 76             pwszDst[i] = pwszDst[i+1];

 77 

 78     wstring wcharString(pwszDst);

 79     delete pwszDst;

 80 

 81     return wcharString;

 82 }

 83 

 84 //-----------------------------------------------------------------------------

 85 //虽然可以转换宽窄字符串，但是不能解决中文乱码问题

 86 std::wstring strtowstr(const std::string &i_str)

 87 {

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

 89     std::wstring l_wstr = conv.from_bytes(i_str);

 90     return l_wstr;

 91 }

 92 std::string wstrtostr(const std::wstring &i_wstr)

 93 {

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

 95     std::string l_str = conv.to_bytes(i_wstr);

 96     return l_str;

 97 }

 98 

 99 //-----------------------------------------------------------------------------

100 bool OutputFile(const string &i_strFileName, const string &i_strExt)

101 {

102     std::locale old_loc = std::locale::global(std::locale(""));

103     ofstream ofs(i_strFileName, ifstream::out|ifstream::binary);

104     if (ofs.rdstate()!=ios_base::goodbit)

105     {

106         cout << "open file error." << endl;

107         return false;

108     }

109     ofs.write(i_strExt.c_str(), i_strExt.length());

110     ofs.clear();

111     ofs.close();

112     std::locale::global(old_loc);

113     return true;

114 }

115 bool OutputFileW(const string &i_strFileName, const wstring &i_wstrExt)

116 {

117     std::locale old_loc = std::locale::global(std::locale(""));

118     wofstream wofs(i_strFileName, ifstream::out|ifstream::binary);

119     if (wofs.rdstate()!=ios_base::goodbit)

120     {

121         wcout << L"open file error." << endl;

122         return false;

123     }

124     wofs.write(i_wstrExt.c_str(), i_wstrExt.length());

125     wofs.clear();

126     wofs.close();

127     std::locale::global(old_loc);

128     return true;

129 }

130 //bool OutputFile2(const string &i_strFileName, const string &i_strExt)

131 //{

132 //    //1

133 //    //std::locale loc("");

134 //    //typedef codecvt<wchar_t, char, std::mbstate_t> facet_type;

135 //    //const std::locale::facet &myfacet = use_facet<facet_type>(loc);

136 //    //std::locale curloc(loc, &myfacet);

137 //

138 //    //std::locale loc("");

139 //    //std::codecvt_utf8_utf16<wchar_t> *pconv = new std::codecvt_utf8_utf16<wchar_t> ();

140 //    //std::locale curloc(loc, pconv);

141 //

142 //    ofstream ofs(i_strFileName, ifstream::out|ifstream::binary);

143 //    if (ofs.rdstate()!=ios_base::goodbit)

144 //    {

145 //        cout << "open file error." << endl;

146 //        return false;

147 //    }

148 //    ofs.imbue(std::locale(std::locale(""), new std::codecvt_utf8_utf16<wchar_t>));

149 //    //ofs.imbue(curloc);

150 //    ofs.write(i_strExt.c_str(), i_strExt.length());

151 //    ofs.clear();

152 //    ofs.close();

153 //

154 //    return true;

155 //}

156 

157 //测试以上代码部分

158 void main()

159 {

160     string strExt = "这是一个窄字符串";

161     wstring wstrExt = L"这是一个宽字符串";

162 

163     //string strRet;

164     //wstring wstrRet;

165     //wstrRet = s2ws(strExt);

166     //strRet = ws2s(wstrExt);

167     //cout << strRet << endl;

168     //wcout << wstrRet << endl;

169 

170     //string strFileName1 = "F:\\Desktop\\20140411\\测试\\output.txt";

171     //bool f1 = OutputFile(strFileName1, strExt);

172     //string strFileName2 = "F:\\Desktop\\20140411\\测试\\outputw.txt";

173     //bool f2 = OutputFileW(strFileName2, wstrExt);

174 

175     //LPCWSTR pwstr = _TEXT("windows宽字符串");

176     //std::string strResult = WChar2Ansi(pwstr);

177     //cout << strResult << endl;

178     //LPCSTR pstr = "windows窄字符串";

179     ////size_t cnlen = lstrlenA(pstr);

180     //size_t cblen = lstrlenA(pstr)*sizeof(CHAR);

181     //std::wstring wstrResult = Ansi2WChar(pstr, cblen);

182     //wcout << wstrResult << endl;

183 

184     //std::wstring wstr = L"wchar_t宽字符";

185     //std::string strResult = wstrtostr(wstr);

186     //cout << "宽字符转窄字符：" << strResult << endl;

187 

188     cout << endl;

189 }