sqlite中文乱码问题解决方案

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，@R_622_7944@，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。

//UTF-8转Unicode
std::wString Utf82Unicode(const std::string& utf8String)
{
int wIDesize = ::MultiBytetoWIDeChar(CP_UTF8,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,&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,wstrcode.c_str(),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,ascIISize,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,(char*)strascii.c_str(),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,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,wIDeString.c_str(),null);
if (utf8size == 0)
{
throw std::exception("Error in conversion.");
}

std::vector<char> resultString(utf8sizE);

int convresult = ::WIDeCharToMultiByte(CP_UTF8,utf8size,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; }