Python正则表达式的几种匹配用法

Question

如题所述

Answer 1

下面列出： 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() 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() 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() 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 ="" 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 ="" 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 = "" 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) 8.遍历所有匹配的子串(Iterate over all matches in a string) for match in re.finditer(r"<(.*?)/s*.*?//1>", subject) # match start: match.start() # match end (exclusive): atch.end() # matched text: match.group() 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) 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() 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() 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() 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 ="" 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 ="" 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 ="" 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) 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()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) 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) 字符串拆分 1.字符串拆分 result = re.split(regex, subject) 2.字符串拆分（使用正则表示式对象） reobj = re.compile(regex) result = reobj.split(subject)