Regular Expressions 101

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/
\{?(?<key>.*?):(?<val>["].*["]?|.*?)[,\W]\}?
/
g
\{
matches the character { with index 12310 (7B16 or 1738) literally (case sensitive)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Named Capture Group key
(?<key>.*?)
.
matches any character (except for line terminators)
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
: matches the character : with index 5810 (3A16 or 728) literally (case sensitive)
Named Capture Group val
(?<val>["].*["]?|.*?)
1st Alternative
["].*["]?
Match a single character present in the list below
["]
" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
["]
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
2nd Alternative
.*?
.
matches any character (except for line terminators)
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
Match a single character present in the list below
[,\W]
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
\W matches any non-word character (equivalent to [^a-zA-Z0-9_])
\}
matches the character } with index 12510 (7D16 or 1758) literally (case sensitive)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Global pattern flags
g modifier: global. All matches (don't return after first match)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
g

Test String