当前位置：首页 > 资讯 > 技术文档

Python正则表达式使用经典实例

时间：2020-12-16 17:37 编辑：来源：阅读：
扫一扫，手机访问

摘要：Python正则表达式使用经典实例

下面列出Python正则表达式的几种匹配用法，具体内容如下所示：此外,关于正则的一切[url=http://deerchao.net/tutorials/regex/regex.htm]http://deerchao.net/tutorials/regex/regex.htm[/url] [b]1.测试正则表达式是否匹配字符串的全部或部分[/b]

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

[b]2.测试正则表达式是否匹配整个字符串[/b]

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

[b]3.创建一个匹配对象[/b]，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()

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

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

[b]5. 获取捕获组所匹配的子串[/b](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 = ""

[b]6. 获取有名组所匹配的子串[/b](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 = ""

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

result = re.findall(regex, subject)

[b]8.遍历所有匹配的子串[/b](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()

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

reobj = re.compile(regex)

[b]10.用法１的正则表达式对象版本[/b]（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()

[b]11.用法２的正则表达式对象版本[/b]（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()

[b]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[/b]（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()

[b]13.用正则表达式对象获取匹配子串（[/b]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 = ""

[b]14.用正则表达式对象获取捕获组所匹配的子串[/b]（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 = ""

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

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

[b]17.通过正则表达式对象遍历所有匹配子串[/b]（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()

[b]字符串替换[/b] [b]1.替换所有匹配的子串[/b]

#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)

[b]2.替换所有匹配的子串（使用正则表达式对象）[/b]

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

[b]字符串拆分[/b] [b]1.字符串拆分[/b]

result = re.split(regex, subject)

[b]2.字符串拆分（使用正则表示式对象）[/b]

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

全部评论(0)

上一篇：Python基于pygame实现图片代替鼠标移动效果
下一篇：浅析Python中else语句块的使用技巧

资讯排行榜
更多>>