sqlite中文乱码问题原因分析及解决

在VC++中通过sqlite3.dll接口对sqlite数据库进行操作，包括打开数据库，插入，查询数据库等，如果操作接口输入参数包含中文字符，会导致操作异常。例如调用sqlite3_open打开数据库文件，如果文件路径出现中文，就会导致打开失败。sqlite3_exec执行sql语句，如果包含中文对应字符就会变成乱码。这是由于sqlite数据库使用的是UTF-8编码方式，而传入的字符串是ASCII编码或Unicode编码，导致字符串格式错误。解决方案是在调用sqlite接口之前，先将字符串转换成UTF-8编码，以下提供各种字符串编码转换函数。 复制代码 代码如下: //UTF-8转Unicode std::wstring Utf82Unicode(const std::string& utf8string) { int widesize = ::MultiByteToWideChar(CP_UTF8, 0, utf8string.c_str(), -1, NULL, 0); if (widesize == ERROR_NO_UNICODE_TRANSLATION) { throw std::exception(\”Invalid UTF-8 sequence.\”); } if (widesize == 0) { throw std::exception(\”Error in conversion.\”); } std::vector<wchar_t> resultstring(widesize); int convresult = ::MultiByteToWideChar(CP_UTF8, 0, utf8string.c_str(), -1, &resultstring[0], widesize); if (convresult != widesize) { throw std::exception(\”La falla!\”); } return std::wstring(&resultstring[0]); } //unicode 转为 ascii string WideByte2Acsi(wstring& wstrcode) { int asciisize = ::WideCharToMultiByte(CP_OEMCP, 0, wstrcode.c_str(), -1, NULL, 0, NULL, NULL); if (asciisize == ERROR_NO_UNICODE_TRANSLATION) { throw std::exception(\”Invalid UTF-8 sequence.\”); } if (asciisize == 0) { throw std::exception(\”Error in conversion.\”); } std::vector<char> resultstring(asciisize); int convresult =::WideCharToMultiByte(CP_OEMCP, 0, wstrcode.c_str(), -1, &resultstring[0], asciisize, NULL, NULL); if (convresult != asciisize) { throw std::exception(\”La falla!\”); } return std::string(&resultstring[0]); } //utf-8 转 ascii string UTF_82ASCII(string& strUtf8Code) { string strRet(\”\”); //先把 utf8 转为 unicode wstring wstr = Utf82Unicode(strUtf8Code); //最后把 unicode 转为 ascii strRet = WideByte2Acsi(wstr); return strRet; } /////////////////////////////////////////////////////////////////////// //ascii 转 Unicode wstring Acsi2WideByte(string& strascii) { int widesize = MultiByteToWideChar (CP_ACP, 0, (char*)strascii.c_str(), -1, NULL, 0); if (widesize == ERROR_NO_UNICODE_TRANSLATION) { throw std::exception(\”Invalid UTF-8 sequence.\”); } if (widesize == 0) { throw std::exception(\”Error in conversion.\”); } std::vector<wchar_t> resultstring(widesize); int convresult = MultiByteToWideChar (CP_ACP, 0, (char*)strascii.c_str(), -1, &resultstring[0], widesize); if (convresult != widesize) { throw std::exception(\”La falla!\”); } return std::wstring(&resultstring[0]); } //Unicode 转 Utf8 std::string Unicode2Utf8(const std::wstring& widestring) { int utf8size = ::WideCharToMultiByte(CP_UTF8, 0, widestring.c_str(), -1, NULL, 0, NULL, NULL); if (utf8size == 0) { throw std::exception(\”Error in conversion.\”); } std::vector<char> resultstring(utf8size); int convresult = ::WideCharToMultiByte(CP_UTF8, 0, widestring.c_str(), -1, &resultstring[0], utf8size, NULL, NULL); if (convresult != utf8size) { throw std::exception(\”La falla!\”); } return std::string(&resultstring[0]); } //ascii 转 Utf8 string ASCII2UTF_8(string& strAsciiCode) { string strRet(\”\”); //先把 ascii 转为 unicode wstring wstr = Acsi2WideByte(strAsciiCode); //最后把 unicode 转为 utf8 strRet = Unicode2Utf8(wstr); return strRet; }