Regular Expressions 101

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<td width=\d* rowspan=\d* align=right><font size=\d* face="helvetica">(?<ThirdNum>\d)<.font><.td>
/
gm
<td width=
matches the characters <td width= literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
rowspan=
matches the characters rowspan= literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
align=right><font size=
matches the characters align=right><font size= literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
face="helvetica">
matches the characters face="helvetica"> literally (case sensitive)
Named Capture Group ThirdNum
(?<ThirdNum>\d)
\d matches a digit (equivalent to [0-9])
< matches the character < with index 6010 (3C16 or 748) literally (case sensitive)
. matches any character (except for line terminators)
font><
matches the characters font>< literally (case sensitive)
. matches any character (except for line terminators)
td>
matches the characters td> literally (case sensitive)
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)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String