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, &resultstrinhttp://www.devze.comg[0], widesize);

ihttp://www.devze.comf (convresult != widesize)

{

throw std::exception("La falla!");

}

return std::whttp://www.devze.comstring(&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_s编程客栈tr(), -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

开发者_NoSQLstrRet = 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, &resul编程客栈tstring[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;

}