RegexOne - Learn Regular Expressions - Lesson 1: An Introduction, and the ABCs

1: abc

2: 123

3: \.

4: [cmf]an

5: [hd]og

6: [A-C]

7: waz{3,5}up

8: aa+b*c+

9: \d+ files? found\?

10: \d\.\s+abc

11: ^Mission: successful$

12: ^(file.+)\.pdf$

13: (\w+ (\d+))

14: (\d+)x(\d+)

15: I love (cats|dogs)

16: .*

hehe :)

Lesson Notes

		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}	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