Regular Expressions 101

Positive Lookbehind(?<=((?<=[\s,.:;"']|^)["']))

Group 1((?<=[\s,.:;"']|^)["'])

Positive Lookbehind(?<=[\s,.:;"']|^)

1st Alternative[\s,.:;"']

Character Class[\s,.:;"']

\sany whitespace character

,the literal , (44₁₀ / 54₈ / 2C₁₆)

.the literal . (46₁₀ / 56₈ / 2E₁₆)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

;the literal ; (59₁₀ / 73₈ / 3B₁₆)

"the literal " (34₁₀ / 42₈ / 22₁₆)

'the literal ' (39₁₀ / 47₈ / 27₁₆)

2nd Alternative^

^start of line

Character Class["']

"the literal " (34₁₀ / 42₈ / 22₁₆)

'the literal ' (39₁₀ / 47₈ / 27₁₆)

Non-Capturing Group(?:(?=(\\?))\2.)*?

*?repeats the group contents below any number of times:

Positive Lookahead(?=(\\?))

Group 2(\\?)

\\?optionally matches the literal \ (92₁₀ / 134₈ / 5C₁₆)

\2the text saved by group 2

.any character (except for line terminators)

Positive Lookahead(?=\1)

\1the text saved by group 1

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

u modifier: unicode. Enables Unicode-aware matching and escape syntax

Detailed match information will be displayed here automatically.

26 tokens

Regular Expression

(?<=((?<=[\s,.:;"']|^)["']))(?:(?=(\\?))\2.)*?(?=\1)

New

Hello world "This is a test"
"This is also an NL test"
'And this has  an escaped quote don\'t  in it ' Blue Boy
"This has a single quote ' but doesn\' end the quote as it started with double quotes"

" Lorem ipsum dolor\" sit 'amet' "

"你好" "こんにちは" "Привет" "हैलो"
"Foo Bar" "Another Value" "HELLO WORLD"