Regular Expressions 101

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^\d+\n\[*\"tb\"
/
^ asserts position at start of the string
\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)
\n matches a line-feed (newline) character (ASCII 10)
\[
matches the character [ with index 9110 (5B16 or 1338) literally (case sensitive)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
tb
matches the characters tb literally (case sensitive)
\" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/

Test String