regex - evanmoran/quick GitHub Wiki

Modifiers

g                 All matches, not just the first
i                 Case-insensitive matching
m                 Multi-line matching

Characters

^                 Beginning
$                 End
*                 Zero or more
+                 One or more
?                 Zero or one
{2}               Two exactly
{2,4}             Between Two and Four
.                 Any character
\s, \S            White space, NOT whitespace. 
\w, \W            Word character, NOT word character. Same as: [a-zA-Z0-9]
\d, \D            Digit character, NOT digit character. Same as: [0-9]
\1, \2, ...       Match previous matches in the expression 
()                Match and remember part of the string. Referred to as \1 \2 etc
(aa|bb)           Match 'aa' or 'bb'
[ab]              Match the character a or b
[^ab]             Match any character except a or b
a(?:b)            Match an a followed by b
a(?=b)            Match an a follow by b (capturing b)
a(?!b)            Match an a not followed by b
a(?!=b)           Match an a not followed by b (capturing b)

Examples

/^abc/            Match string that starts with 'abc'
/abc$/            Match string that ends with 'abc'
/abc/g            Match all 'abc' strings
/abc/i            Match the first 'abc' strings of any case
/(['"])\w+\1/     Match word surrounded by quotes of the same type