Regular Expressions 101

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`
(?:contact-us/support-for-client-administrators/glossary)(?:/)?(?:.*[^0-9a-zA-Z].*)?(?:\\.aspx)?$
`
gmi
Non-capturing group
(?:contact-us/support-for-client-administrators/glossary)
contact-us/support-for-client-administrators/glossary
matches the characters contact-us/support-for-client-administrators/glossary literally (case insensitive)
Non-capturing group
(?:/)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
/ matches the character / with index 4710 (2F16 or 578) literally (case insensitive)
Non-capturing group
(?:.*[^0-9a-zA-Z].*)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
.
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 not present in the list below
[^0-9a-zA-Z]
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case insensitive)
a-z matches a single character in the range between a (index 97) and z (index 122) (case insensitive)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case insensitive)
.
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)
Non-capturing group
(?:\\.aspx)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\\ matches the character \ with index 9210 (5C16 or 1348) literally (case insensitive)
. matches any character (except for line terminators)
aspx
matches the characters aspx literally (case insensitive)
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
Your regular expression does not match the subject string.

Regular Expression
No Match

`
`
gmi

Test String