Regular Expressions 101

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/
^\s*\d+\s*$(?:\r?\n?)+^\s*([\d:,\.]+)\s*-->\s*([\d:,\.]+)\s*$(?:\r?\n?)+((?:.*(?:\r?\n?)?)*?)(?:\r\n|\r|\n|$)
/
^ asserts position at start of the string
\s
matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of the string
Non-capturing group
(?:\r?\n?)+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\r
matches a carriage return (ASCII 13)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\n
matches a line-feed (newline) character (ASCII 10)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
^ asserts position at start of the string
\s
matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
1st Capturing Group
([\d:,\.]+)
Match a single character present in the list below
[\d:,\.]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\d matches a digit (equivalent to [0-9])
:,
matches a single character in the list :, (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
-->
matches the characters --> literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Capturing Group
([\d:,\.]+)
Match a single character present in the list below
[\d:,\.]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\d matches a digit (equivalent to [0-9])
:,
matches a single character in the list :, (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of the string
Non-capturing group
(?:\r?\n?)+
3rd Capturing Group
((?:.*(?:\r?\n?)?)*?)
Non-capturing group
(?:\r\n|\r|\n|$)
Your regular expression does not match the subject string.

Regular Expression
No Match

/
/

Test String