常见python正则用法的简单实例

下面列出Python正则表达式的几种匹配用法：

1.测试正则表达式是否匹配字符串的全部或部分

regex=ur"" #正则表达式if re.search(regex, subject):do_something()else:do_anotherthing()

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2.测试正则表达式是否匹配整个字符串

regex=ur"Z" #正则表达式末尾以Z结束if re.match(regex, subject):    do_something()else:    do_anotherthing()

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3.创建一个匹配对象，然后通过该对象获得匹配细节(Create an object with details about how the regex matches (part of) a string)

regex=ur"" #正则表达式match = re.search(regex, subject)if match:    # match start: match.start()    # match end (exclusive): atch.end()    # matched text: match.group()    do_something()else:    do_anotherthing()

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4.获取正则表达式所匹配的子串(Get the part of a string matched by the regex)

regex=ur"" #正则表达式match = re.search(regex, subject)if match:    result = match.group()else:    result = ""

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5. 获取捕获组所匹配的子串(Get the part of a string matched by a capturing group)

regex=ur"" #正则表达式match = re.search(regex, subject)if match:    result = match.group(1)else:    result = ""

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6. 获取有名组所匹配的子串(Get the part of a string matched by a named group)

regex=ur"" #正则表达式match = re.search(regex, subject)if match:result = match.group"groupname")else:result = ""

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7. 将字符串中所有匹配的子串放入数组中(Get an array of all regex matches in a string)

result = re.findall(regex, subject)

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8.遍历所有匹配的子串(Iterate over all matches in a string)

for match in re.finditer(r"", subject)    # match start: match.start()    # match end (exclusive): atch.end()    # matched text: match.group()

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9.通过正则表达式字符串创建一个正则表达式对象(Create an object to use the same regex for many operations)

reobj = re.compile(regex)

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10.用法１的正则表达式对象版本（use regex object for if/else branch whether (part of) a string can be matched）

reobj = re.compile(regex)if reobj.search(subject):    do_something()else:    do_anotherthing()

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11.用法２的正则表达式对象版本（use regex object for if/else branch whether a string can be matched entirely）

reobj = re.compile(r"Z")　＃正则表达式末尾以Z 结束if reobj.match(subject):    do_something()else:    do_anotherthing()

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12.创建一个正则表达式对象，然后通过该对象获得匹配细节（Create an object with details about how the regex object matches (part of) a string）

reobj = re.compile(regex)match = reobj.search(subject)if match:    # match start: match.start()    # match end (exclusive): atch.end()    # matched text: match.group()    do_something()else:    do_anotherthing()

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13.用正则表达式对象获取匹配子串（Use regex object to get the part of a string matched by the regex）

reobj = re.compile(regex)match = reobj.search(subject)if match:    result = match.group()else:    result = ""

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14.用正则表达式对象获取捕获组所匹配的子串（Use regex object to get the part of a string matched by a capturing group）

reobj = re.compile(regex)match = reobj.search(subject)if match:    result = match.group(1)else:    result = ""

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15.用正则表达式对象获取有名组所匹配的子串（Use regex object to get the part of a string matched by a named group）

reobj = re.compile(regex)match = reobj.search(subject)if match:    result = match.group("groupname")else:    result = ""

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16.用正则表达式对象获取所有匹配子串并放入数组（Use regex object to get an array of all regex matches in a string）

reobj = re.compile(regex)result = reobj.findall(subject)

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17.通过正则表达式对象遍历所有匹配子串（Use regex object to iterate over all matches in a string）

reobj = re.compile(regex)for match in reobj.finditer(subject):    # match start: match.start()    # match end (exclusive): match.end()    # matched text: match.group()

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字符串替换

1.替换所有匹配的子串

#用newstring替换subject中所有与正则表达式regex匹配的子串result = re.sub(regex, newstring, subject)

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2.替换所有匹配的子串（使用正则表达式对象）

reobj = re.compile(regex)result = reobj.sub(newstring, subject)

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字符串拆分

1.字符串拆分

result = re.split(regex, subject)

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2.字符串拆分（使用正则表示式对象）

reobj = re.compile(regex)result = reobj.split(subject)

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以上这篇常见python正则用法的简单实例就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持脚本之家。