Python regex note

To remember Python regex easily, we organise Python regex notes from concrete to abstract, and from simple to sophisticate D.

I, Important character:

1, quantitive character:

? : [0,1], *:[0,INFI), +:(0,infi), {N}:[n rep], {m,}:[m, infi), {, n}:[0,n], {m,n}:[m,n],

? (nogreedy option)

2, Begin and End:

^: Beginning, $: ending

3, Making own character class:

[ABC], [^ABC]: ^ Rep non
4, Character classes:

\d,\d,\s,\s,\w,\w
5:dot (or wildcard) character:

. , 　　.*,　　(.*) ? : Rep Nongreedy Fashion

II, usefull regex arguments

1, Re. Dotall:match all characters, including the newline character.

2, Re. I (re. IGNORECASE): Ignore uppercase

3, Re. Verbose:spread the regex over multiple lines with comments.

4, | : We could use pipe character to cobine all three above arguments.

III, generate Regex procedure:

1, regex = Re.compile (r "")

2.1.1, Regex.search ("")

2.1.2, Regex.search (""). Group (), (or Regex.search (""). Group (No)), greedy Defalut

2.2, Regex.findall ("")

2.3 Regex.sub ("")

3, Re.compile (r "" (

　　　　　　　　　　

) ", Re. VERBOSE): To manage more complex regrexes.

6:re. Dotall, Re. I

Python regex note