Regular Expressions 101

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/
( xmlns:?[^=]*=[""][^""]*[""])
/
g
1st Capturing Group
( xmlns:?[^=]*=[""][^""]*[""])
xmlns
matches the characters xmlns literally (case sensitive)
:
matches the character : with index 5810 (3A16 or 728) literally (case sensitive)
Match a single character not present in the list below
[^=]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Match a single character present in the list below
[""]
""
matches a single character in the list " (case sensitive)
Match a single character not present in the list below
[^""]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
""
matches a single character in the list " (case sensitive)
Match a single character present in the list below
[""]
""
matches a single character in the list " (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
g

Test String