Shulou(Shulou.com)06/02 Report--

This article mainly shows you "how to use regular expressions in Python", the content is easy to understand, clear, hope to help you solve doubts, the following let Xiaobian lead you to study and learn "how to use regular expressions in Python" this article.

1. What is a regular expression?

It's simply a kind of string matching, eg: for example, when you sign up for an account, we need to determine whether the user's user name is legitimate, then we need to search the user's input, or give you a 5-11-digit number to determine whether it is a qq number.

2.1 using the regular expression import re2.2 matching principle import remsg = 'Miss Dong bridge girl' pattern = re.compile ('Miss Dong') result = pattern.match (msg) print (result) print (result.group ()) # returns the matching content print (result.span ()) # returns the matching position # common method msg1 = 'Miss Dong bridge girl Miss South' result1 = re.search ('Miss South') Msg1) print (result1) print (result1.span ()) # return position print (result1.group ()) # returns matching content

First, the compile () method compiles the regular expression into an object, and then processes the string using the method of the regular expression object. However, it is not so troublesome. When you use the function directly, it is already compiled, and you do not need to use the complie method (). Then you can use the group () method to get the matching content, and the span () method to get the matching position.

2.3.Common functions match match from scratch. If there is no match, return Noneseach to match from scratch. Query all strings and return the string that matches first. Sub searches for matching content and then replaces it. Findall finds all the satisfying strings and returns a list. Split uses characters that conform to the regular expression as delimiters, splits the string and returns a list.

The above is all the content of the article "how to use regular expressions in Python". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.