前言
正则表达式在字符匹配是不可或缺的,也是非常重要的,需要我们熟练掌握。
常用字符匹配方法
- abc… Letters
- 123… Digits
- \d Any Digit
- \D Any Non-digit character
- . Any Character
- . Period
- [abc] Only a, b, or c
- [^abc] Not a, b, nor c
- [a-z] Characters a to z
- [0-9] Numbers 0 to 9
- \w Any Alphanumeric character
- \W Any Non-alphanumeric character
- m Repetitions
- {m,n} m to n Repetitions
- * Zero or more repetitions
- + One or more repetitions
- ? Optional character
- \s Any Whitespace
- \S Any Non-whitespace character
- ^…$ Starts and ends
- (…) Capture Group
- (a(bc)) Capture Sub-group
- (.*) Capture all
- (abc|def) Matches abc or def