Regular Expressions 101

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/
^(\d{2})\/(\d{2})\/(\d{4}) (\d{2}):(\d{2})$
/
^ asserts position at start of the string
1st Capturing Group
(\d{2})
\d
matches a digit (equivalent to [0-9])
{2} matches the previous token exactly 2 times
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
2nd Capturing Group
(\d{2})
\d
matches a digit (equivalent to [0-9])
{2} matches the previous token exactly 2 times
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
3rd Capturing Group
(\d{4})
\d
matches a digit (equivalent to [0-9])
{4} matches the previous token exactly 4 times
matches the character with index 3210 (2016 or 408) literally (case sensitive)
4th Capturing Group
(\d{2})
\d
matches a digit (equivalent to [0-9])
{2} matches the previous token exactly 2 times
: matches the character : with index 5810 (3A16 or 728) literally (case sensitive)
5th Capturing Group
(\d{2})
\d
matches a digit (equivalent to [0-9])
{2} matches the previous token exactly 2 times
$ asserts position at the end of the string, or before the line terminator right at the end of the string (if any)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/

Test String