我得到了一个错误与以下异常消息:
UnicodeEncodeError: 'ascii' codec can't encode character u'\ufeff' in position 155: ordinal not in range(128)
不确定u'\ufeff'是什么,它在我进行网络抓取时出现。我该如何补救这种情况呢?.replace()字符串方法对它不起作用。
u'\ufeff'
.replace()
该字符是物料清单或“字节顺序标记”。它通常作为文件的前几个字节接收,告诉您如何解释其余数据的编码。您可以简单地删除字符继续。不过,由于错误提示您正在尝试转换为'ascii',您可能应该为您正在尝试做的任何事情选择另一种编码。
您抓取的内容是用unicode而不是ascii文本编码的,因此您得到的字符不能转换为ascii。正确的“翻译”取决于原始网页认为它是什么。Python的unicode页面给出了它如何工作的背景。
您是试图打印结果还是将其粘贴到文件中?该错误表明是写作数据导致了问题,而不是读取它。这个问题是一个寻找修复的好地方。
Unicode字符U+FEFF是字节顺序标记,或BOM,用于区分大端和小端UTF-16编码之间的区别。如果您使用正确的编解码器解码网页,Python将为您删除它。例子:
U+FEFF
#!python2 #coding: utf8 u = u'ABC' e8 = u.encode('utf-8') # encode without BOM e8s = u.encode('utf-8-sig') # encode with BOM e16 = u.encode('utf-16') # encode with BOM e16le = u.encode('utf-16le') # encode without BOM e16be = u.encode('utf-16be') # encode without BOM print 'utf-8 %r' % e8 print 'utf-8-sig %r' % e8s print 'utf-16 %r' % e16 print 'utf-16le %r' % e16le print 'utf-16be %r' % e16be print print 'utf-8 w/ BOM decoded with utf-8 %r' % e8s.decode('utf-8') print 'utf-8 w/ BOM decoded with utf-8-sig %r' % e8s.decode('utf-8-sig') print 'utf-16 w/ BOM decoded with utf-16 %r' % e16.decode('utf-16') print 'utf-16 w/ BOM decoded with utf-16le %r' % e16.decode('utf-16le')
注意EF BB BF是一个utf -8编码的BOM。对于UTF-8,它不是必需的,但仅作为签名(通常在Windows上)。
EF BB BF
输出:
utf-8 'ABC' utf-8-sig '\xef\xbb\xbfABC' utf-16 '\xff\xfeA\x00B\x00C\x00' # Adds BOM and encodes using native processor endian-ness. utf-16le 'A\x00B\x00C\x00' utf-16be '\x00A\x00B\x00C' utf-8 w/ BOM decoded with utf-8 u'\ufeffABC' # doesn't remove BOM if present. utf-8 w/ BOM decoded with utf-8-sig u'ABC' # removes BOM if present. utf-16 w/ BOM decoded with utf-16 u'ABC' # *requires* BOM to be present. utf-16 w/ BOM decoded with utf-16le u'\ufeffABC' # doesn't remove BOM if present.
注意,要给出utf-16编解码器需要 BOM,否则Python将不知道数据是大端还是小端。
utf-16
如果没有它,BOM将包含在读取结果中:
>>> f = open('file', mode='r') >>> f.read() '\ufefftest'
给出正确的编码,结果中省略BOM:
>>> f = open('file', mode='r', encoding='utf-8-sig') >>> f.read() 'test'
这只是我的个人意见。
以下是基于Mark Tolonen的回答。字符串包含单词“test”的不同语言,用“|”分隔,所以你可以看到区别。
u = u'ABCtestβ貝塔위másbêta|test|اختبار|测试|測試|テスト|परीक्षा|പരിശോധന|פּרובירן|kiểm tra|Ölçek|' e8 = u.encode('utf-8') # encode without BOM e8s = u.encode('utf-8-sig') # encode with BOM e16 = u.encode('utf-16') # encode with BOM e16le = u.encode('utf-16le') # encode without BOM e16be = u.encode('utf-16be') # encode without BOM print('utf-8 %r' % e8) print('utf-8-sig %r' % e8s) print('utf-16 %r' % e16) print('utf-16le %r' % e16le) print('utf-16be %r' % e16be) print() print('utf-8 w/ BOM decoded with utf-8 %r' % e8s.decode('utf-8')) print('utf-8 w/ BOM decoded with utf-8-sig %r' % e8s.decode('utf-8-sig')) print('utf-16 w/ BOM decoded with utf-16 %r' % e16.decode('utf-16')) print('utf-16 w/ BOM decoded with utf-16le %r' % e16.decode('utf-16le'))
下面是一个测试:
>>> u = u'ABCtestβ貝塔위másbêta|test|اختبار|测试|測試|テスト|परीक्षा|പരിശോധന|פּרובירן|kiểm tra|Ölçek|' >>> e8 = u.encode('utf-8') # encode without BOM >>> e8s = u.encode('utf-8-sig') # encode with BOM >>> e16 = u.encode('utf-16') # encode with BOM >>> e16le = u.encode('utf-16le') # encode without BOM >>> e16be = u.encode('utf-16be') # encode without BOM >>> print('utf-8 %r' % e8) utf-8 b'ABCtest\xce\xb2\xe8\xb2\x9d\xe5\xa1\x94\xec\x9c\x84m\xc3\xa1sb\xc3\xaata|test|\xd8\xa7\xd8\xae\xd8\xaa\xd8\xa8\xd8\xa7\xd8\xb1|\xe6\xb5\x8b\xe8\xaf\x95|\xe6\xb8\xac\xe8\xa9\xa6|\xe3\x83\x86\xe3\x82\xb9\xe3\x83\x88|\xe0\xa4\xaa\xe0\xa4\xb0\xe0\xa5\x80\xe0\xa4\x95\xe0\xa5\x8d\xe0\xa4\xb7\xe0\xa4\xbe|\xe0\xb4\xaa\xe0\xb4\xb0\xe0\xb4\xbf\xe0\xb4\xb6\xe0\xb5\x8b\xe0\xb4\xa7\xe0\xb4\xa8|\xd7\xa4\xd6\xbc\xd7\xa8\xd7\x95\xd7\x91\xd7\x99\xd7\xa8\xd7\x9f|ki\xe1\xbb\x83m tra|\xc3\x96l\xc3\xa7ek|' >>> print('utf-8-sig %r' % e8s) utf-8-sig b'\xef\xbb\xbfABCtest\xce\xb2\xe8\xb2\x9d\xe5\xa1\x94\xec\x9c\x84m\xc3\xa1sb\xc3\xaata|test|\xd8\xa7\xd8\xae\xd8\xaa\xd8\xa8\xd8\xa7\xd8\xb1|\xe6\xb5\x8b\xe8\xaf\x95|\xe6\xb8\xac\xe8\xa9\xa6|\xe3\x83\x86\xe3\x82\xb9\xe3\x83\x88|\xe0\xa4\xaa\xe0\xa4\xb0\xe0\xa5\x80\xe0\xa4\x95\xe0\xa5\x8d\xe0\xa4\xb7\xe0\xa4\xbe|\xe0\xb4\xaa\xe0\xb4\xb0\xe0\xb4\xbf\xe0\xb4\xb6\xe0\xb5\x8b\xe0\xb4\xa7\xe0\xb4\xa8|\xd7\xa4\xd6\xbc\xd7\xa8\xd7\x95\xd7\x91\xd7\x99\xd7\xa8\xd7\x9f|ki\xe1\xbb\x83m tra|\xc3\x96l\xc3\xa7ek|' >>> print('utf-16 %r' % e16) utf-16 b"\xff\xfeA\x00B\x00C\x00t\x00e\x00s\x00t\x00\xb2\x03\x9d\x8cTX\x04\xc7m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x00'\x06.\x06*\x06(\x06'\x061\x06|\x00Km\xd5\x8b|\x00,nf\x8a|\x00\xc60\xb90\xc80|\x00*\t0\t@\t\x15\tM\t7\t>\t|\x00*\r0\r?\r6\rK\r'\r(\r|\x00\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x05|\x00k\x00i\x00\xc3\x1em\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|\x00" >>> print('utf-16le %r' % e16le) utf-16le b"A\x00B\x00C\x00t\x00e\x00s\x00t\x00\xb2\x03\x9d\x8cTX\x04\xc7m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x00'\x06.\x06*\x06(\x06'\x061\x06|\x00Km\xd5\x8b|\x00,nf\x8a|\x00\xc60\xb90\xc80|\x00*\t0\t@\t\x15\tM\t7\t>\t|\x00*\r0\r?\r6\rK\r'\r(\r|\x00\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x05|\x00k\x00i\x00\xc3\x1em\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|\x00" >>> print('utf-16be %r' % e16be) utf-16be b"\x00A\x00B\x00C\x00t\x00e\x00s\x00t\x03\xb2\x8c\x9dXT\xc7\x04\x00m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x06'\x06.\x06*\x06(\x06'\x061\x00|mK\x8b\xd5\x00|n,\x8af\x00|0\xc60\xb90\xc8\x00|\t*\t0\t@\t\x15\tM\t7\t>\x00|\r*\r0\r?\r6\rK\r'\r(\x00|\x05\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x00|\x00k\x00i\x1e\xc3\x00m\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|" >>> print() >>> print('utf-8 w/ BOM decoded with utf-8 %r' % e8s.decode('utf-8')) utf-8 w/ BOM decoded with utf-8 '\ufeffABCtestβ貝塔위másbêta|test|اختبار|测试|測試|テスト|परीक्षा|പരിശോധന|פּרובירן|kiểm tra|Ölçek|' >>> print('utf-8 w/ BOM decoded with utf-8-sig %r' % e8s.decode('utf-8-sig')) utf-8 w/ BOM decoded with utf-8-sig 'ABCtestβ貝塔위másbêta|test|اختبار|测试|測試|テスト|परीक्षा|പരിശോധന|פּרובירן|kiểm tra|Ölçek|' >>> print('utf-16 w/ BOM decoded with utf-16 %r' % e16.decode('utf-16')) utf-16 w/ BOM decoded with utf-16 'ABCtestβ貝塔위másbêta|test|اختبار|测试|測試|テスト|परीक्षा|പരിശോധന|פּרובירן|kiểm tra|Ölçek|' >>> print('utf-16 w/ BOM decoded with utf-16le %r' % e16.decode('utf-16le')) utf-16 w/ BOM decoded with utf-16le '\ufeffABCtestβ貝塔위másbêta|test|اختبار|测试|測試|テスト|परीक्षा|പരിശോധന|פּרובירן|kiểm tra|Ölçek|'
值得注意的是,在encode和decode之后,只有utf-8-sig和utf-16会返回原始字符串。
encode
decode
utf-8-sig