unicode 转GBK为什么要这样转，哪位能解释一下么。

grant

[mw_shl_code=c,true]WCHAR ff_convert ( /* Converted code, 0 means conversion error */ WCHAR src, /* Character code to be converted */ UINT dir /* 0: Unicode to OEMCP, 1: OEMCP to Unicode */ ) { WCHAR t[2]; WCHAR c; u32 i, li, hi; u16 n; u32 gbk2uni_offset=0; if (src < 0x80)c = src;//ASCII,直接不用转换. else { if(dir) //GBK 2 UNICODE { gbk2uni_offset=ftinfo.ugbksize/2; }else //UNICODE 2 GBK { gbk2uni_offset=0; } /* Unicode to OEMCP */ hi=ftinfo.ugbksize/2;//对半开. hi =hi / 4 - 1; li = 0; for (n = 16; n; n--) { i = li + (hi - li) / 2; SPI_Flash_Read((u8*)&t,ftinfo.ugbkaddr+i*4+gbk2uni_offset,4);//读出4个字节 if (src == t[0]) break; if (src > t[0])li = i; else hi = i; } c = n ? t[1] : 0; } return c; } [/mw_shl_code]

正点原子

因为转换数组就是这么设计的。