Regular Expressions 101

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/
^([s|S][e|E][l|L][e|E][c|C][t|T])\s([a-zA-Z0-9\-_]+|\*),?([a-zA-Z0-9\-_]+)*\s([f|F][r|R][o|O][m|M])\s([a-zA-Z0-9\-_]+|\*),?([a-zA-Z0-9\-_]+)*(.*);$
/
^ asserts position at start of the string
1st Capturing Group
([s|S][e|E][l|L][e|E][c|C][t|T])
Match a single character present in the list below
[s|S]
s|S
matches a single character in the list s|S (case sensitive)
Match a single character present in the list below
[e|E]
e|E
matches a single character in the list e|E (case sensitive)
Match a single character present in the list below
[l|L]
l|L
matches a single character in the list l|L (case sensitive)
Match a single character present in the list below
[e|E]
e|E
matches a single character in the list e|E (case sensitive)
Match a single character present in the list below
[c|C]
c|C
matches a single character in the list c|C (case sensitive)
Match a single character present in the list below
[t|T]
t|T
matches a single character in the list t|T (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
2nd Capturing Group
([a-zA-Z0-9\-_]+|\*)
1st Alternative
[a-zA-Z0-9\-_]+
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 4510 (2D16 or 558) literally (case sensitive)
_ matches the character _ with index 9510 (5F16 or 1378) literally (case sensitive)
2nd Alternative
\*
\* matches the character * with index 4210 (2A16 or 528) literally (case sensitive)
,
matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
3rd Capturing Group
([a-zA-Z0-9\-_]+)*
* matches the previous token between zero 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 4510 (2D16 or 558) literally (case sensitive)
_ matches the character _ with index 9510 (5F16 or 1378) literally (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
4th Capturing Group
([f|F][r|R][o|O][m|M])
Match a single character present in the list below
[f|F]
f|F
matches a single character in the list f|F (case sensitive)
Match a single character present in the list below
[r|R]
r|R
matches a single character in the list r|R (case sensitive)
Match a single character present in the list below
[o|O]
o|O
matches a single character in the list o|O (case sensitive)
Match a single character present in the list below
[m|M]
m|M
matches a single character in the list m|M (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
5th Capturing Group
([a-zA-Z0-9\-_]+|\*)
1st Alternative
[a-zA-Z0-9\-_]+
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 4510 (2D16 or 558) literally (case sensitive)
_ matches the character _ with index 9510 (5F16 or 1378) literally (case sensitive)
2nd Alternative
\*
\* matches the character * with index 4210 (2A16 or 528) literally (case sensitive)
,
matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
6th Capturing Group
([a-zA-Z0-9\-_]+)*
* matches the previous token between zero 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 4510 (2D16 or 558) literally (case sensitive)
_ matches the character _ with index 9510 (5F16 or 1378) literally (case sensitive)
7th Capturing Group
(.*)
.
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)
; matches the character ; with index 5910 (3B16 or 738) literally (case sensitive)
$ 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