c 项目使用sqlite中文乱码问题-ag真人官方网

理论是：sqlite使用的是utf-8，c 中用的字符串是ascii或unicode编码。

         所以使用时候要进行转化。插入中文时候要转化为utf-8，读取时候再转化回来。

    //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 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 
    std::string widebyte2acsi(std::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 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 
    std::string utf_82ascii(std::string& strutf8code){
        using namespace std;
        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 
    std::wstring acsi2widebyte(std::string& strascii){
        using namespace std;
        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 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){
        using namespace std;
        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 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 
    std::string ascii2utf_8(std::string& strasciicode) {
        using namespace std;
        string strret("");
        //先把 ascii 转为 unicode 
        wstring wstr = acsi2widebyte(strasciicode);
        //最后把 unicode 转为 utf8 
        strret = unicode2utf8(wstr);
        return strret;
    }

使用效果立竿见影：

可以看出，之前存进数据库的是乱码

改变之后已经成功将汉字存进去了