Regular Expressions 101

Pro

1st Alternative(href="([^"]+).*(?=img src))

Group 1(href="([^"]+).*(?=img src))

href="the literal text href=" (case sensitive)

Group 2([^"]+)

Negated Character Class[^"]+

+matches at least one character outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

.*any character (except for line terminators), repeated any number of times

Positive Lookahead(?=img src)

img srcthe literal text img src (case sensitive)

2nd Alternative(img src="([^"]*))

Group 3(img src="([^"]*))

img src="the literal text img src=" (case sensitive)

Group 4([^"]*)

Negated Character Class[^"]*

*matches any number of characters outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

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

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

(href="([^"]+).*(?=img src))|(img src="([^"]*))

New

<a href="I NEED THIS1">  <img src="I NEED THIS2">  </a>  
<a href="I DONT NEED THIS" title="something">  </a>   
<a href="I NEED THIS3" title="blah"> <figure> <img src="I NEED THIS4" alt="">   </figure>  </a>

Substitution

<a href="I NEED THIS1">  <img src="I NEED THIS2">  </a>  
<a href="I DONT NEED THIS" title="something">  </a>   
<a href="I NEED THIS3" title="blah"> <figure> <img src="I NEED THIS4" alt="">   </figure>  </a>