Regular Expressions 101

\ban ASCII word boundary

Group date(?P<date>(?P<day>3[0-1]|[0-2]?[\d])(?P<separator>\/|\-|\.)(?P<month>1[0-2]|[0-1]?[\d])\3(?P<year>[\d]{4}|[\d]{2}))

Group day(?P<day>3[0-1]|[0-2]?[\d])

1st Alternative3[0-1]

3the literal 3 (51₁₀ / 63₈ / 33₁₆)

Character Class[0-1]

0-1one character from 0 (48₁₀) to 1 (49₁₀)

2nd Alternative[0-2]?[\d]

Character Class[0-2]?

?matches at most one character from the set below:

0-2one character from 0 (48₁₀) to 2 (50₁₀)

Character Class[\d]

\da digit

Group separator(?P<separator>\/|\-|\.)

1st Alternative\/

\/the literal / (47₁₀ / 57₈ / 2F₁₆)

2nd Alternative\-

\-the literal - (45₁₀ / 55₈ / 2D₁₆)

3rd Alternative\.

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group month(?P<month>1[0-2]|[0-1]?[\d])

1st Alternative1[0-2]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[0-2]

0-2one character from 0 (48₁₀) to 2 (50₁₀)

2nd Alternative[0-1]?[\d]

Character Class[0-1]?

?matches at most one character from the set below:

0-1one character from 0 (48₁₀) to 1 (49₁₀)

Character Class[\d]

\da digit

\3the text saved by group 3

Group year(?P<year>[\d]{4}|[\d]{2})

1st Alternative[\d]{4}

Character Class[\d]{4}

{4}matches exactly 4 characters from the set below:

\da digit

2nd Alternative[\d]{2}

Character Class[\d]{2}

{2}matches exactly 2 characters from the set below:

\da digit

Global pattern flags

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

\b(?P<date>(?P<day>3[0-1]|[0-2]?[\d])(?P<separator>\/|\-|\.)(?P<month>1[0-2]|[0-1]?[\d])\3(?P<year>[\d]{4}|[\d]{2}))

New

este es el 22/11/2015 o el 8/2/1982 o el 9-5-2012 o tal vez el 10.10.15 mas que 9-5-12 tdo

Regular Expression

Substitution