关于stringWithContentsOfURL

//这一段代码返回网页的内容。

    NSURL *url = [NSURL URLWithString:@"http://api.showji.com/locating/only_test.aspx?m=13437158888&outfmt=json&outenc=gb18030"];

    NSString *pageContent = [NSString stringWithContentsOfURL:url encoding:0x80000632 error:nil];

    NSLog(@"%@",pageContent);

    

    //下面这段代码有时候返回的和上面的一样，有时候是网页地址，为什么？

    NSURL *apiUrl = [NSURL URLWithString:@"http://public.phate.tw/myip/"];

    NSString *pageLoc = [NSString stringWithContentsOfURL:apiUrl];

    NSLog(@"%@",pageLoc);

    const NSStringEncoding *encodings = [NSString availableStringEncodings];

    NSStringEncoding encoding;

    int i = 0;

    while ((encoding = *encodings++) != 0) {

        NSLog(@"%d: %@ == 0x%x\n", i++, [NSString localizedNameOfStringEncoding:encoding], encoding);

    }

打印如下：

2009-06-08 23:12:44.420 MoviePre[1243:20b] 0: Western (Mac OS Roman) == 0x1e

2009-06-08 23:12:44.421 MoviePre[1243:20b] 1: Japanese (Mac OS) == 0x80000001

2009-06-08 23:12:44.421 MoviePre[1243:20b] 2: Traditional Chinese (Mac OS) == 0x80000002

2009-06-08 23:12:44.422 MoviePre[1243:20b] 3: Korean (Mac OS) == 0x80000003

2009-06-08 23:12:44.422 MoviePre[1243:20b] 4: Arabic (Mac OS) == 0x80000004

2009-06-08 23:12:44.432 MoviePre[1243:20b] 5: Hebrew (Mac OS) == 0x80000005

2009-06-08 23:12:44.433 MoviePre[1243:20b] 6: Greek (Mac OS) == 0x80000006

2009-06-08 23:12:44.433 MoviePre[1243:20b] 7: Cyrillic (Mac OS) == 0x80000007

2009-06-08 23:12:44.436 MoviePre[1243:20b] 8: Devanagari (Mac OS) == 0x80000009

2009-06-08 23:12:44.447 MoviePre[1243:20b] 9: Gurmukhi (Mac OS) == 0x8000000a

2009-06-08 23:12:44.447 MoviePre[1243:20b] 10: Gujarati (Mac OS) == 0x8000000b

2009-06-08 23:12:44.447 MoviePre[1243:20b] 11: Thai (Mac OS) == 0x80000015

2009-06-08 23:12:44.448 MoviePre[1243:20b] 12: Simplified Chinese (Mac OS) == 0x80000019

2009-06-08 23:12:44.448 MoviePre[1243:20b] 13: Tibetan (Mac OS) == 0x8000001a

2009-06-08 23:12:44.452 MoviePre[1243:20b] 14: Central European (Mac OS) == 0x8000001d

2009-06-08 23:12:44.453 MoviePre[1243:20b] 15: Symbol (Mac OS) == 0x6

2009-06-08 23:12:44.455 MoviePre[1243:20b] 16: Dingbats (Mac OS) == 0x80000022

2009-06-08 23:12:44.455 MoviePre[1243:20b] 17: Turkish (Mac OS) == 0x80000023

2009-06-08 23:12:44.456 MoviePre[1243:20b] 18: Croatian (Mac OS) == 0x80000024

2009-06-08 23:12:44.464 MoviePre[1243:20b] 19: Icelandic (Mac OS) == 0x80000025

2009-06-08 23:12:44.467 MoviePre[1243:20b] 20: Romanian (Mac OS) == 0x80000026

2009-06-08 23:12:44.467 MoviePre[1243:20b] 21: Celtic (Mac OS) == 0x80000027

2009-06-08 23:12:44.468 MoviePre[1243:20b] 22: Gaelic (Mac OS) == 0x80000028

2009-06-08 23:12:44.469 MoviePre[1243:20b] 23: Keyboard Symbols (Mac OS) == 0x80000029

2009-06-08 23:12:44.469 MoviePre[1243:20b] 24: Farsi (Mac OS) == 0x8000008c

2009-06-08 23:12:44.470 MoviePre[1243:20b] 25: Cyrillic (Mac OS Ukrainian) == 0x80000098

2009-06-08 23:12:44.470 MoviePre[1243:20b] 26: Inuit (Mac OS) == 0x800000ec

2009-06-08 23:12:44.471 MoviePre[1243:20b] 27: Unicode (UTF-32LE) == 0x9c000100

2009-06-08 23:12:44.471 MoviePre[1243:20b] 28: Unicode (UTF-8) == 0x4

2009-06-08 23:12:44.472 MoviePre[1243:20b] 29: Unicode (UTF-16) == 0xa

2009-06-08 23:12:44.473 MoviePre[1243:20b] 30: Unicode (UTF-16BE) == 0x90000100

2009-06-08 23:12:44.473 MoviePre[1243:20b] 31: Unicode (UTF-16LE) == 0x94000100

2009-06-08 23:12:44.480 MoviePre[1243:20b] 32: Unicode (UTF-32) == 0x8c000100

2009-06-08 23:12:44.480 MoviePre[1243:20b] 33: Unicode (UTF-32BE) == 0x98000100

2009-06-08 23:12:44.481 MoviePre[1243:20b] 34: Western (ISO Latin 1) == 0x5

2009-06-08 23:12:44.481 MoviePre[1243:20b] 35: Central European (ISO Latin 2) == 0x9

2009-06-08 23:12:44.481 MoviePre[1243:20b] 36: Western (ISO Latin 3) == 0x80000203

2009-06-08 23:12:44.482 MoviePre[1243:20b] 37: Central European (ISO Latin 4) == 0x80000204

2009-06-08 23:12:44.493 MoviePre[1243:20b] 38: Cyrillic (ISO 8859-5) == 0x80000205

2009-06-08 23:12:44.493 MoviePre[1243:20b] 39: Arabic (ISO 8859-6) == 0x80000206

2009-06-08 23:12:44.494 MoviePre[1243:20b] 40: Greek (ISO 8859-7) == 0x80000207

2009-06-08 23:12:44.494 MoviePre[1243:20b] 41: Hebrew (ISO 8859-8) == 0x80000208

2009-06-08 23:12:44.495 MoviePre[1243:20b] 42: Turkish (ISO Latin 5) == 0x80000209

2009-06-08 23:12:44.495 MoviePre[1243:20b] 43: Nordic (ISO Latin 6) == 0x8000020a

2009-06-08 23:12:44.506 MoviePre[1243:20b] 44: Thai (ISO 8859-11) == 0x8000020b

2009-06-08 23:12:44.507 MoviePre[1243:20b] 45: Baltic Rim (ISO Latin 7) == 0x8000020d

2009-06-08 23:12:44.510 MoviePre[1243:20b] 46: Celtic (ISO Latin 8) == 0x8000020e

2009-06-08 23:12:44.511 MoviePre[1243:20b] 47: Western (ISO Latin 9) == 0x8000020f

2009-06-08 23:12:44.511 MoviePre[1243:20b] 48: Romanian (ISO Latin 10) == 0x80000210

2009-06-08 23:12:44.512 MoviePre[1243:20b] 49: Latin-US (DOS) == 0x80000400

2009-06-08 23:12:44.512 MoviePre[1243:20b] 50: Greek (DOS) == 0x80000405

2009-06-08 23:12:44.513 MoviePre[1243:20b] 51: Baltic Rim (DOS) == 0x80000406

2009-06-08 23:12:44.513 MoviePre[1243:20b] 52: Western (DOS Latin 1) == 0x80000410

2009-06-08 23:12:44.513 MoviePre[1243:20b] 53: Greek (DOS Greek 1) == 0x80000411

2009-06-08 23:12:44.514 MoviePre[1243:20b] 54: Central European (DOS Latin 2) == 0x80000412

2009-06-08 23:12:44.514 MoviePre[1243:20b] 55: Cyrillic (DOS) == 0x80000413

2009-06-08 23:12:44.514 MoviePre[1243:20b] 56: Turkish (DOS) == 0x80000414

2009-06-08 23:12:44.515 MoviePre[1243:20b] 57: Portuguese (DOS) == 0x80000415

2009-06-08 23:12:44.516 MoviePre[1243:20b] 58: Icelandic (DOS) == 0x80000416

2009-06-08 23:12:44.517 MoviePre[1243:20b] 59: Hebrew (DOS) == 0x80000417

2009-06-08 23:12:44.517 MoviePre[1243:20b] 60: Canadian French (DOS) == 0x80000418

2009-06-08 23:12:44.517 MoviePre[1243:20b] 61: Arabic (DOS) == 0x80000419

2009-06-08 23:12:44.518 MoviePre[1243:20b] 62: Nordic (DOS) == 0x8000041a

2009-06-08 23:12:44.518 MoviePre[1243:20b] 63: Russian (DOS) == 0x8000041b

2009-06-08 23:12:44.519 MoviePre[1243:20b] 64: Greek (DOS Greek 2) == 0x8000041c

2009-06-08 23:12:44.519 MoviePre[1243:20b] 65: Thai (Windows, DOS) == 0x8000041d

2009-06-08 23:12:44.520 MoviePre[1243:20b] 66: Japanese (Windows, DOS) == 0x8

2009-06-08 23:12:44.522 MoviePre[1243:20b] 67: Simplified Chinese (Windows, DOS) == 0x80000421

2009-06-08 23:12:44.522 MoviePre[1243:20b] 68: Korean (Windows, DOS) == 0x80000422

2009-06-08 23:12:44.524 MoviePre[1243:20b] 69: Traditional Chinese (Windows, DOS) == 0x80000423

2009-06-08 23:12:44.524 MoviePre[1243:20b] 70: Western (Windows Latin 1) == 0xc

2009-06-08 23:12:44.525 MoviePre[1243:20b] 71: Central European (Windows Latin 2) == 0xf

2009-06-08 23:12:44.525 MoviePre[1243:20b] 72: Cyrillic (Windows) == 0xb

2009-06-08 23:12:44.525 MoviePre[1243:20b] 73: Greek (Windows) == 0xd

2009-06-08 23:12:44.526 MoviePre[1243:20b] 74: Turkish (Windows Latin 5) == 0xe

2009-06-08 23:12:44.526 MoviePre[1243:20b] 75: Hebrew (Windows) == 0x80000505

2009-06-08 23:12:44.526 MoviePre[1243:20b] 76: Arabic (Windows) == 0x80000506

2009-06-08 23:12:44.527 MoviePre[1243:20b] 77: Baltic Rim (Windows) == 0x80000507

2009-06-08 23:12:44.529 MoviePre[1243:20b] 78: Vietnamese (Windows) == 0x80000508

2009-06-08 23:12:44.531 MoviePre[1243:20b] 79: Western (ASCII) == 0x1

2009-06-08 23:12:44.532 MoviePre[1243:20b] 80: Japanese (Shift JIS X0213) == 0x80000628

2009-06-08 23:12:44.533 MoviePre[1243:20b] 81: Chinese (GBK) == 0x80000631

2009-06-08 23:12:44.534 MoviePre[1243:20b] 82: Chinese (GB 18030) == 0x80000632

2009-06-08 23:12:44.534 MoviePre[1243:20b] 83: Japanese (ISO 2022-JP) == 0x15

2009-06-08 23:12:44.535 MoviePre[1243:20b] 84: Korean (ISO 2022-KR) == 0x80000840

2009-06-08 23:12:44.536 MoviePre[1243:20b] 85: Japanese (EUC) == 0x3

2009-06-08 23:12:44.536 MoviePre[1243:20b] 86: Simplified Chinese (EUC) == 0x80000930

2009-06-08 23:12:44.538 MoviePre[1243:20b] 87: Traditional Chinese (EUC) == 0x80000931

2009-06-08 23:12:44.539 MoviePre[1243:20b] 88: Korean (EUC) == 0x80000940

2009-06-08 23:12:44.540 MoviePre[1243:20b] 89: Japanese (Shift JIS) == 0x80000a01

2009-06-08 23:12:44.541 MoviePre[1243:20b] 90: Cyrillic (KOI8-R) == 0x80000a02

2009-06-08 23:12:44.541 MoviePre[1243:20b] 91: Traditional Chinese (Big 5) == 0x80000a03

2009-06-08 23:12:44.541 MoviePre[1243:20b] 92: Western (Mac Mail) == 0x80000a04

2009-06-08 23:12:44.542 MoviePre[1243:20b] 93: Simplified Chinese (HZ GB 2312) == 0x80000a05

2009-06-08 23:12:44.542 MoviePre[1243:20b] 94: Traditional Chinese (Big 5 HKSCS) == 0x80000a06

2009-06-08 23:12:44.542 MoviePre[1243:20b] 95: Ukrainian (KOI8-U) == 0x80000a08

2009-06-08 23:12:44.546 MoviePre[1243:20b] 96: Traditional Chinese (Big 5-E) == 0x80000a09

2009-06-08 23:12:44.547 MoviePre[1243:20b] 97: Western (NextStep) == 0x2

2009-06-08 23:12:44.547 MoviePre[1243:20b] 98: Non-lossy ASCII == 0x7

2009-06-08 23:12:44.548 MoviePre[1243:20b] 99: Western (EBCDIC US) == 0x80000c01

2009-06-08 23:12:44.548 MoviePre[1243:20b] 100: Western (EBCDIC Latin 1) == 0x80000c02
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