Group AttributeName(?<AttributeName>(?:src|background)) Non-Capturing Group(?:src|background) srcthe literal text src (case sensitive) 2nd Alternativebackground backgroundthe literal text background (case sensitive) \s*any whitespace character, repeated any number of times
=the literal = (6110 / 758 / 3D16)
\s*any whitespace character, repeated any number of times
"the literal " (3410 / 428 / 2216)
'the literal ' (3910 / 478 / 2716)
Group AttributeValue(?<AttributeValue>(?:[^"'])*) Non-Capturing Group(?:[^"'])* *repeats the group contents below any number of times:
Negated Character Class[^"'] "the literal " (3410 / 428 / 2216)
'the literal ' (3910 / 478 / 2716)
g modifier: global. Finds all matches instead of stopping after the first