\uff081\uff09re.sub(‘ROAD$’, ‘RD. ‘, s)#$\u5339\u914d\u5728\u7ed3\u5c3e\u7684\u5b57\u7b26\u4e32\uff0c^\u5339\u914d\u5728\u5f00\u5934\u7684\u5b57\u7b26\u4e32\u3002re.sub\u662f\u5728s\u5b57\u7b26\u4e32\u7684\u7ed3\u5c3e\uff0c\u67e5\u627e’ROAD$’\uff0c\u7136\u540e\u7528 ‘RD. ‘\u66ff\u6362\u3002<\/p>\n
\uff082\uff09re.sub(r’\\bROAD\\b’, ‘RD. ‘, s)#\\b\u8868\u793a\u4e00\u4e2a\u8bcd\u7684\u8fb9\u754c\u5728\u8fd9\u91cc\u3002\u4f46’\\’\u9700\u8981\u4e00\u4e2a’\\’\u8fdb\u884c\u8f6c\u610f\uff0c\u4e0d\u7136\\b\u4f1a\u88ab\u8ba4\u4e3a\u662f\u4e00\u4e2a\u5b57\u7b26\u3002\u5982\u679c\u4e0d\u60f3\u8fdb\u884c\u8f6c\u610f\u8981\u4f7f\u7528\u4e00\u79cd\u53eb\u505a\u201c\u751f\u5b57\u7b26\u4e32\u201d\uff0c\u65b9\u6cd5\u662f\u5728\u5b57\u7b26\u4e32\u4e4b\u524d\u52a0\u4e0a\u4e00\u4e2ar\uff0c\u5982’\\t’\u4ee3\u8868tab\u5b57\u7b26\uff0c\u4f46r’\\t’\u5b83\u4ee3\u8868\u4e24\u4e2a\u5b57\u7b26\u3002\u5efa\u8bae\u5728\u4ee3\u6709\u6b63\u5219\u8868\u8fbe\u5f0f\u7684\u5b57\u7b26\u4e32\u4f7f\u7528\u201c\u751f\u5b57\u7b26\u4e32\u201d\uff0c\u53ef\u4ee5\u907f\u514d\u8868\u8fbe\u5f0f\u592a\u590d\u6742\u800c\u964d\u4f4e\u4e86\u901f\u5ea6\u3002<\/span><\/p>\n \uff083\uff09\u95ee\u53f7\uff08\uff1f\uff09\u7528\u4e8e\u5339\u914d\u81f3\u591a\u4e00\u6b21\u5b83\u4e4b\u524d\u7684\u9879\uff1b\u661f\u53f7\uff08*\uff09\u7528\u4e8e\u5339\u914d0\u6216\u591a\u6b21\u4e4b\u524d\u7684\u9879\uff1b\u52a0\u53f7\uff08+\uff09\u7528\u4e8e\u5339\u914d1\u6216\u591a\u6b21\u4e4b\u524d\u7684\u9879\uff1b\u70b9\u53f7\uff08.\uff09\u9664\u4e86\u6362\u884c\u7b26\u7684\u4efb\u610f\u5b57\u7b26\u3002<\/p>\n \uff084\uff09re\u6a21\u5757\u7684\u6838\u5fc3\u672c\u8d28\u5c31\u662fsearch()\u51fd\u6570\uff1a \uff085\uff09pattern=’^M?M?M?(CM|CD|D?C?C?C?)$’ \uff086\uff09pattern = ‘^M{0,3}$’#\u8fd9\u4e2a\u6a21\u5f0f\u662f\u8bf4\uff1a\u5339\u914d\u5f00\u5934\u5b57\u7b26\u4e320\u81f33\u4e2aM\u5b57\u7b26\uff0c\u5e76\u4e14\u7ed3\u5c3e\u4e5f\u662f\u5982\u6b64\u3002\u548c’^M?M?M?$’\u8fd9\u4e2a\u6a21\u5f0f\u76f8\u540c\u3002<\/p>\n \uff087\uff09\u6b63\u5219\u8868\u8fbe\u5f0f\u5206\u4e3a\u201c\u7cbe\u7b80\u6a21\u5f0f\u201d\u548c\u201c\u5197\u4f59\u6a21\u5f0f\u201d\uff0c\u5b83\u4eec\u4e4b\u95f4\u7684\u4e0d\u540c\u662f\uff1a<\/p>\n \uff088\uff09 \uff089\uff09\u65b9\u62ec\u53f7[]\uff1a<\/p>\n \uff0810\uff09findall(pattern, string)\u51fd\u6570\uff0c\u5728string\u4e2d\u627e\u5230\u6240\u6709\u7b26\u5408pattern\u7684\u5b57\u7b26\uff0c\u5e76\u8fd4\u56de\u4e00\u4e2a\u5217\u8868\uff1a \uff0811\uff09\u5339\u914d\u6700\u77ed\u53ef\u80fd\u7684\u4efb\u610f\u5b57\u7b26\u4e32\uff08.*?\uff09 \uff0812\uff09<\/p>\n","protected":false},"excerpt":{"rendered":" \uff081\uff09re.sub(‘ROAD$’, ‘RD. ‘, s)#$\u5339\u914d\u5728\u7ed3\u5c3e\u7684\u5b57\u7b26\u4e32\uff0c^\u5339\u914d\u5728\u5f00\u5934\u7684\u5b57\u7b26\u4e32\u3002re.s…<\/p>\n
\nre.search(‘^M?M?M?$’, ‘MMMM’)#\u65e0\u6cd5\u5339\u914d\u5230\uff0c\u56e0\u4e3a\u8981\u6c42\u5339\u914d0~3\u4e2aM\u5f00\u5934\u5e76\u7ed3\u5c3e\u7684\u5b57\u7b26\uff0c\u5176\u5b9e\u5c31\u662f\u5b8c\u5168\u5339\u914d0~3\u4e2aM\uff0c0~3\u4e2aM\u4e0d\u80fd\u5728\u5b57\u7b26\u4e32\u7684\u4e2d\u95f4\u51fa\u73b0\u3002
\nre.search(‘^M?M?M?$’, ”)#\u53ef\u4ee5\u5339\u914d\u5230\uff0c\u56e0\u4e3a\u53ef\u4ee5\u662f0\u4e2aM\uff01<\/p>\n
\n\u8fd9\u4e2a\u6a21\u5f0f\u5206\u62ec\u53f7\u91cc\u7684\u5185\u5bb9\u662f\u4e00\u9879\uff0c\u4e0d\u53ef\u5206\u5272\u7684\u4e00\u7ec4\u5185\u5bb9\uff0c\u5b83\u7684\u5185\u5bb9\u4ee3\u8868\u4e00\u79cd\u53ef\u80fd\uff0c\u7528\u7ad6\u7ebf\u5206\u5f00\uff08|\uff09\uff0c\u53ef\u4ee5\u662f\uff1aCM\uff0cCD\u6216D?C?C?C?\u3002\u6240\u4ee5\uff1a<\/p>\n\n
\n
\n
\n>>>pattern = ”’
\n^\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # beginning of string
\nM{0,3} \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0\u00a0 # thousands – 0 to 3 Ms
\n(CM|CD|D?C{0,3})\u00a0\u00a0 # hundreds – 900 (CM), 400 (CD), 0-300 (0 to 3 Cs),
\n# or 500-800 (D, followed by 0 to 3 Cs)
\n(XC|XL|L?X{0,3})\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # tens – 90 (XC), 40 (XL), 0-30 (0 to 3 Xs),
\n# or 50-80 (L, followed by 0 to 3 Xs)
\n(IX|IV|V?I{0,3})\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # ones – 9 (IX), 4 (IV), 0-3 (0 to 3 Is),
\n# or 5-8 (V, followed by 0 to 3 Is)
\n$\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 # end of string
\n”’
\n>>>re.search(pattern, ‘M’, re.VERBOSE)
\n\u53ef\u4ee5\u5339\u914d\u5230\u5185\u5bb9<\/li>\n<\/ul>\n
\n>>> phonePattern = re.compile(r’^(\\d{3})-(\\d{3})-(\\d{4})$’)
\n>>> phonePattern.search(‘800-555-1212’).groups()
\n(‘800’, ‘555’, ‘1212’)
\ngroups()\u65b9\u6cd5\u53ef\u4ee5\u5c06\u8fd4\u56de\u4e00\u4e2a\u5143\u7ec4\uff08tuple\uff09\uff0c\u662f\u5728\u6b63\u5219\u8868\u8fbe\u5f0f\u4e2d\u5b9a\u4e49\u597d\u7684\u5206\u7ec4\uff0c\u6bcf\u4e2a\u5206\u7ec4\u90fd\u662f\u7528\u62ec\u53f7\u62ec\u8d77\u6765\u7684\u3002
\n\uff08PS:search()\u548cgroups()\u4e0d\u8981\u8fde\u5728\u4e00\u8d77\u7528\uff0c\u56e0\u4e3a\u5f53\u6ca1\u6709\u5339\u914d\u5230\u5185\u5bb9\u65f6\uff0csearch()\u4f1a\u8fd4\u56deNone\uff0c\u800cNone\u662f\u6ca1\u6709groups()\u65b9\u6cd5\u7684\uff0c\u8fd9\u65f6\u4f1a\u5f15\u53d1\u4e00\u4e2a\u5f02\u5e38<\/span>\uff0c\u5982\uff1a
\n>>> pattern = r’^(\\d{3})-(\\d{3})-(\\d{4})-?(\\d{4})?$’
\n>>> re.search(pattern, ‘800-555-12df’).groups()
\nTraceback (most recent call last):
\nFile “<stdin>”, line 1, in <module>
\nAttributeError: ‘NoneType’ object has no attribute ‘groups’\uff09<\/p>\n\n
\n>>> import re<\/code>
\n>>> re.findall('[0-9]+', '16 2-by-4s in rows of 8') \u2460<\/code>
\n['16', '2', '4', '8'<\/code><\/p>\n
\n>>> re.findall(' s.*? s', \"The sixth s<\/span>ick sheikh's s<\/span>ixth sheep's s<\/span>ick.\")<\/code>
\n[' sixth s', \" sheikh's s\", \" sheep's s\"]<\/code><\/p>\n