Regular Expressions 101

Pro

Group 1(20\d{2})

20the literal text 20

\d{2}a digit, repeated exactly 2 times

Group 2(\d{2})

\d{2}a digit, repeated exactly 2 times

Group 3(\d{2})

\d{2}a digit, repeated exactly 2 times

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

(20\d{2})(\d{2})(\d{2})

New

aaa_20150229_bbb
aaa_20120229_bbb
aaa_20000229_bbb
aaa_19000229_bbb
aaa_18000229_bbb
aaa_17000229_bbb
aaa_16000229_bbb

aaa_20150130_bbb
aaa_20150131_bbb
aaa_20150430_bbb
aaa_20150431_bbb

Substitution

aaa_20150229_bbb
aaa_20120229_bbb
aaa_20000229_bbb
aaa_19000229_bbb
aaa_18000229_bbb
aaa_17000229_bbb
aaa_16000229_bbb

aaa_20150130_bbb
aaa_20150131_bbb
aaa_20150430_bbb
aaa_20150431_bbb