Regular Expressions 101

^start of line

Group 1(0[0-9]|1[0-9]|2[1-4])

1st Alternative0[0-9]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

2nd Alternative1[0-9]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

3rd Alternative2[1-4]

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[1-4]

1-4one character from 1 (49₁₀) to 4 (52₁₀)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 2(0[0-9]|[1-5][0-9])

1st Alternative0[0-9]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

2nd Alternative[1-5][0-9]

Character Class[1-5]

1-5one character from 1 (49₁₀) to 5 (53₁₀)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 3(0[0-9]|[1-5][0-9])

1st Alternative0[0-9]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

2nd Alternative[1-5][0-9]

Character Class[1-5]

1-5one character from 1 (49₁₀) to 5 (53₁₀)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

$end of line

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.

Search reference

Regular Expression

^(0[0-9]|1[0-9]|2[1-4]):(0[0-9]|[1-5][0-9]):(0[0-9]|[1-5][0-9])$

New

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// You can show origina post on albertcolom.com/blog