字符串与UTF_8的相互转换

//功能： 将Unicode字串转换为UTF8字串//参数：//strDownloadInfo: 要下载的app的信息(Unicode类型)//返回值：//成功返回转换后的UTF8的string字串，失败则返回空字串string UnicodeConversionUTF8(string strDownloadInfo){stringstrResurt;// 返回的结构字符串DWORDdwStrlen = 0;// 要获取的字节数的大小char *strNew = NULL;__try{if (0 == strDownloadInfo.size()){__leave;}if ((dwStrlen=::WideCharToMultiByte(CP_UTF8,0,CA2W(strDownloadInfo.data()),-1,NULL,0,NULL,NULL))==0){__leave;}  strNew = new char[dwStrlen+1]; if (NULL == strNew){__leave;}if (0 == ::WideCharToMultiByte(CP_UTF8,0,CA2W(strDownloadInfo.data()),-1,strNew,dwStrlen,NULL,NULL)){__leave;}strResurt = strNew;}__finally{if (strNew != NULL){delete[] strNew;}}return strResurt;}// 功能：将UTF8字节转换为Unicode编码的字符串// 参数：//strUtf:要转换的UTF8的编码字符串// 返回值：//成功后返回Unicode编码的字符串，失败则返回空字符串string UTF8ConversionUnicode(string strUtf){stringstrResurt;// 返回的结构字符串DWORDdwStrlen = 0;// 要获取的字节数的大小WCHAR*strNew = NULL;__try{if (0 == strUtf.size()){__leave;}if (0 == (dwStrlen=::MultiByteToWideChar(CP_UTF8,0,strUtf.data(),-1,NULL,0))){__leave;}  strNew = new WCHAR[dwStrlen+1]; if (NULL == strNew){__leave;}ZeroMemory(strNew,sizeof(TCHAR)*(dwStrlen+1));if (0 == ::MultiByteToWideChar(CP_UTF8,0,strUtf.data(),-1,strNew,dwStrlen)){__leave;}strResurt = CW2A(strNew);}__finally{if (strNew != NULL){delete[] strNew;}}return strResurt;}