Regular Expressions 101

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`
((\.{2}\/{1})+|((\.{1}\/{1})?)|(\/{1}))(([a-zA-Z0-9]+\/{1})+)([a-zA-Z0-9])+(\.{1}[a-zA-Z0-9]+)?$
`
1st Capturing Group
((\.{2}\/{1})+|((\.{1}\/{1})?)|(\/{1}))
1st Alternative
(\.{2}\/{1})+
2nd Capturing Group
(\.{2}\/{1})+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
\.
matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
{2} matches the previous token exactly 2 times
\/
matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
{1} matches the previous token exactly one time (meaningless quantifier)
2nd Alternative
((\.{1}\/{1})?)
3rd Capturing Group
((\.{1}\/{1})?)
4th Capturing Group
(\.{1}\/{1})?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\.
matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
{1} matches the previous token exactly one time (meaningless quantifier)
\/
matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
{1} matches the previous token exactly one time (meaningless quantifier)
3rd Alternative
(\/{1})
5th Capturing Group
(\/{1})
\/
matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
{1} matches the previous token exactly one time (meaningless quantifier)
6th Capturing Group
(([a-zA-Z0-9]+\/{1})+)
7th Capturing Group
([a-zA-Z0-9]+\/{1})+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character present in the list below
[a-zA-Z0-9]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
\/
matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
{1} matches the previous token exactly one time (meaningless quantifier)
8th Capturing Group
([a-zA-Z0-9])+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character present in the list below
[a-zA-Z0-9]
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
9th Capturing Group
(\.{1}[a-zA-Z0-9]+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\.
matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
{1} matches the previous token exactly one time (meaningless quantifier)
Match a single character present in the list below
[a-zA-Z0-9]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
$ asserts position at the end of the string
Your regular expression does not match the subject string.

Regular Expression
No Match

`
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Test String