NSString 的非utf-8编码（gbk，gb18030）

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博文原创，转载请声明出处

电子咖啡(原id蓝岩)

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ios系统盒max os系统默认是utf-8编码的，有时候我们获得的资源是gbk的，因此需要将字符串进行转码。代码如下：

  unsigned long encode = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingGB_18030_2000);    NSString* str = @"张三"; //这里是你的gbk编码string    NSData *responseData =[str dataUsingEncoding:NSUTF8StringEncoding ];    NSString *str_gb18030 = [[NSString alloc] initWithData:responseData encoding:encode];    NSLog(@"str_gb18030=%@", str_gb18030);

另附上ios支持的所有编码：

{/*  kCFStringEncodingMacRoman = 0L, defined in CoreFoundation/CFString.h */    kCFStringEncodingMacJapanese = 1,    kCFStringEncodingMacChineseTrad = 2,    kCFStringEncodingMacKorean = 3,    kCFStringEncodingMacArabic = 4,    kCFStringEncodingMacHebrew = 5,    kCFStringEncodingMacGreek = 6,    kCFStringEncodingMacCyrillic = 7,    kCFStringEncodingMacDevanagari = 9,    kCFStringEncodingMacGurmukhi = 10,    kCFStringEncodingMacGujarati = 11,    kCFStringEncodingMacOriya = 12,    kCFStringEncodingMacBengali = 13,    kCFStringEncodingMacTamil = 14,    kCFStringEncodingMacTelugu = 15,    kCFStringEncodingMacKannada = 16,    kCFStringEncodingMacMalayalam = 17,    kCFStringEncodingMacSinhalese = 18,    kCFStringEncodingMacBurmese = 19,    kCFStringEncodingMacKhmer = 20,    kCFStringEncodingMacThai = 21,    kCFStringEncodingMacLaotian = 22,    kCFStringEncodingMacGeorgian = 23,    kCFStringEncodingMacArmenian = 24,    kCFStringEncodingMacChineseSimp = 25,    kCFStringEncodingMacTibetan = 26,    kCFStringEncodingMacMongolian = 27,    kCFStringEncodingMacEthiopic = 28,    kCFStringEncodingMacCentralEurRoman = 29,    kCFStringEncodingMacVietnamese = 30,    kCFStringEncodingMacExtArabic = 31,    /* The following use script code 0, smRoman */    kCFStringEncodingMacSymbol = 33,    kCFStringEncodingMacDingbats = 34,    kCFStringEncodingMacTurkish = 35,    kCFStringEncodingMacCroatian = 36,    kCFStringEncodingMacIcelandic = 37,    kCFStringEncodingMacRomanian = 38,    kCFStringEncodingMacCeltic = 39,    kCFStringEncodingMacGaelic = 40,    /* The following use script code 4, smArabic */    kCFStringEncodingMacFarsi = 0x8C,/* Like MacArabic but uses Farsi digits */    /* The following use script code 7, smCyrillic */    kCFStringEncodingMacUkrainian = 0x98,    /* The following use script code 32, smUnimplemented */    kCFStringEncodingMacInuit = 0xEC,    kCFStringEncodingMacVT100 = 0xFC,/* VT100/102 font from Comm Toolbox: Latin-1 repertoire + box drawing etc */    /* Special Mac OS encodings*/    kCFStringEncodingMacHFS = 0xFF,/* Meta-value, should never appear in a table */    /* Unicode & ISO UCS encodings begin at 0x100 */    /* We don't use Unicode variations defined in TextEncoding; use the ones in CFString.h, instead. */    /* ISO 8-bit and 7-bit encodings begin at 0x200 *//*  kCFStringEncodingISOLatin1 = 0x0201, defined in CoreFoundation/CFString.h */    kCFStringEncodingISOLatin2 = 0x0202,/* ISO 8859-2 */    kCFStringEncodingISOLatin3 = 0x0203,/* ISO 8859-3 */    kCFStringEncodingISOLatin4 = 0x0204,/* ISO 8859-4 */    kCFStringEncodingISOLatinCyrillic = 0x0205,/* ISO 8859-5 */    kCFStringEncodingISOLatinArabic = 0x0206,/* ISO 8859-6, =ASMO 708, =DOS CP 708 */    kCFStringEncodingISOLatinGreek = 0x0207,/* ISO 8859-7 */    kCFStringEncodingISOLatinHebrew = 0x0208,/* ISO 8859-8 */    kCFStringEncodingISOLatin5 = 0x0209,/* ISO 8859-9 */    kCFStringEncodingISOLatin6 = 0x020A,/* ISO 8859-10 */    kCFStringEncodingISOLatinThai = 0x020B,/* ISO 8859-11 */    kCFStringEncodingISOLatin7 = 0x020D,/* ISO 8859-13 */    kCFStringEncodingISOLatin8 = 0x020E,/* ISO 8859-14 */    kCFStringEncodingISOLatin9 = 0x020F,/* ISO 8859-15 */    kCFStringEncodingISOLatin10 = 0x0210,/* ISO 8859-16 */    /* MS-DOS & Windows encodings begin at 0x400 */    kCFStringEncodingDOSLatinUS = 0x0400,/* code page 437 */    kCFStringEncodingDOSGreek = 0x0405,/* code page 737 (formerly code page 437G) */    kCFStringEncodingDOSBalticRim = 0x0406,/* code page 775 */    kCFStringEncodingDOSLatin1 = 0x0410,/* code page 850, "Multilingual" */    kCFStringEncodingDOSGreek1 = 0x0411,/* code page 851 */    kCFStringEncodingDOSLatin2 = 0x0412,/* code page 852, Slavic */    kCFStringEncodingDOSCyrillic = 0x0413,/* code page 855, IBM Cyrillic */    kCFStringEncodingDOSTurkish = 0x0414,/* code page 857, IBM Turkish */    kCFStringEncodingDOSPortuguese = 0x0415,/* code page 860 */    kCFStringEncodingDOSIcelandic = 0x0416,/* code page 861 */    kCFStringEncodingDOSHebrew = 0x0417,/* code page 862 */    kCFStringEncodingDOSCanadianFrench = 0x0418, /* code page 863 */    kCFStringEncodingDOSArabic = 0x0419,/* code page 864 */    kCFStringEncodingDOSNordic = 0x041A,/* code page 865 */    kCFStringEncodingDOSRussian = 0x041B,/* code page 866 */    kCFStringEncodingDOSGreek2 = 0x041C,/* code page 869, IBM Modern Greek */    kCFStringEncodingDOSThai = 0x041D,/* code page 874, also for Windows */    kCFStringEncodingDOSJapanese = 0x0420,/* code page 932, also for Windows */    kCFStringEncodingDOSChineseSimplif = 0x0421, /* code page 936, also for Windows */    kCFStringEncodingDOSKorean = 0x0422,/* code page 949, also for Windows; Unified Hangul Code */    kCFStringEncodingDOSChineseTrad = 0x0423,/* code page 950, also for Windows *//*  kCFStringEncodingWindowsLatin1 = 0x0500, defined in CoreFoundation/CFString.h */    kCFStringEncodingWindowsLatin2 = 0x0501,/* code page 1250, Central Europe */    kCFStringEncodingWindowsCyrillic = 0x0502,/* code page 1251, Slavic Cyrillic */    kCFStringEncodingWindowsGreek = 0x0503,/* code page 1253 */    kCFStringEncodingWindowsLatin5 = 0x0504,/* code page 1254, Turkish */    kCFStringEncodingWindowsHebrew = 0x0505,/* code page 1255 */    kCFStringEncodingWindowsArabic = 0x0506,/* code page 1256 */    kCFStringEncodingWindowsBalticRim = 0x0507,/* code page 1257 */    kCFStringEncodingWindowsVietnamese = 0x0508, /* code page 1258 */    kCFStringEncodingWindowsKoreanJohab = 0x0510, /* code page 1361, for Windows NT */    /* Various national standards begin at 0x600 *//*  kCFStringEncodingASCII = 0x0600, defined in CoreFoundation/CFString.h */    kCFStringEncodingANSEL = 0x0601,/* ANSEL (ANSI Z39.47) */    kCFStringEncodingJIS_X0201_76 = 0x0620,    kCFStringEncodingJIS_X0208_83 = 0x0621,    kCFStringEncodingJIS_X0208_90 = 0x0622,    kCFStringEncodingJIS_X0212_90 = 0x0623,    kCFStringEncodingJIS_C6226_78 = 0x0624,    kCFStringEncodingShiftJIS_X0213 CF_ENUM_AVAILABLE(10_5, 2_0) = 0x0628, /* Shift-JIS format encoding of JIS X0213 planes 1 and 2*/    kCFStringEncodingShiftJIS_X0213_MenKuTen = 0x0629,/* JIS X0213 in plane-row-column notation */    kCFStringEncodingGB_2312_80 = 0x0630,    kCFStringEncodingGBK_95 = 0x0631,/* annex to GB 13000-93; for Windows 95 */    kCFStringEncodingGB_18030_2000 = 0x0632,    kCFStringEncodingKSC_5601_87 = 0x0640,/* same as KSC 5601-92 without Johab annex */    kCFStringEncodingKSC_5601_92_Johab = 0x0641, /* KSC 5601-92 Johab annex */    kCFStringEncodingCNS_11643_92_P1 = 0x0651,/* CNS 11643-1992 plane 1 */    kCFStringEncodingCNS_11643_92_P2 = 0x0652,/* CNS 11643-1992 plane 2 */    kCFStringEncodingCNS_11643_92_P3 = 0x0653,/* CNS 11643-1992 plane 3 (was plane 14 in 1986 version) */    /* ISO 2022 collections begin at 0x800 */    kCFStringEncodingISO_2022_JP = 0x0820,    kCFStringEncodingISO_2022_JP_2 = 0x0821,    kCFStringEncodingISO_2022_JP_1 = 0x0822, /* RFC 2237*/    kCFStringEncodingISO_2022_JP_3 = 0x0823, /* JIS X0213*/    kCFStringEncodingISO_2022_CN = 0x0830,    kCFStringEncodingISO_2022_CN_EXT = 0x0831,    kCFStringEncodingISO_2022_KR = 0x0840,    /* EUC collections begin at 0x900 */    kCFStringEncodingEUC_JP = 0x0920,/* ISO 646, 1-byte katakana, JIS 208, JIS 212 */    kCFStringEncodingEUC_CN = 0x0930,/* ISO 646, GB 2312-80 */    kCFStringEncodingEUC_TW = 0x0931,/* ISO 646, CNS 11643-1992 Planes 1-16 */    kCFStringEncodingEUC_KR = 0x0940,/* ISO 646, KS C 5601-1987 */    /* Misc standards begin at 0xA00 */    kCFStringEncodingShiftJIS = 0x0A01,/* plain Shift-JIS */    kCFStringEncodingKOI8_R = 0x0A02,/* Russian internet standard */    kCFStringEncodingBig5 = 0x0A03,/* Big-5 (has variants) */    kCFStringEncodingMacRomanLatin1 = 0x0A04,/* Mac OS Roman permuted to align with ISO Latin-1 */    kCFStringEncodingHZ_GB_2312 = 0x0A05,/* HZ (RFC 1842, for Chinese mail & news) */    kCFStringEncodingBig5_HKSCS_1999 = 0x0A06, /* Big-5 with Hong Kong special char set supplement*/    kCFStringEncodingVISCII = 0x0A07,/* RFC 1456, Vietnamese */    kCFStringEncodingKOI8_U = 0x0A08,/* RFC 2319, Ukrainian */    kCFStringEncodingBig5_E = 0x0A09,/* Taiwan Big-5E standard */    /* Other platform encodings*//*  kCFStringEncodingNextStepLatin = 0x0B01, defined in CoreFoundation/CFString.h */    kCFStringEncodingNextStepJapanese = 0x0B02,/* NextStep Japanese encoding */    /* EBCDIC & IBM host encodings begin at 0xC00 */    kCFStringEncodingEBCDIC_US = 0x0C01,/* basic EBCDIC-US */    kCFStringEncodingEBCDIC_CP037 = 0x0C02,/* code page 037, extended EBCDIC (Latin-1 set) for US,Canada... */    kCFStringEncodingUTF7 CF_ENUM_AVAILABLE(10_6, 4_0) = 0x04000100, /* kTextEncodingUnicodeDefault + kUnicodeUTF7Format RFC2152 */    kCFStringEncodingUTF7_IMAP CF_ENUM_AVAILABLE(10_6, 4_0) = 0x0A10, /* UTF-7 (IMAP folder variant) RFC3501 */    /* Deprecated constants */    kCFStringEncodingShiftJIS_X0213_00 = 0x0628 /* Shift-JIS format encoding of JIS X0213 planes 1 and 2 (DEPRECATED) */}