RegEx - Time Validation ((h)h:mm)

Question

/^\\d{1,2}[:][0-5][0-9]$/

is what I have. this limits minutes to 00-59. It does not, however, limit hours to between 0 and 12. For similarity and unifo

Answer 1

The 0 - 9 and 10 - 12 cases need to be treated separately. (The two rules can be combined with |.)

/^(?:0?\d|1[012]):[0-5]\d$/

Here

• (?:…) is a non-capturing group
• x|y means match either pattern
• 0?\d matches 0 - 9 or 00 - 09
• 1[012] matches 10 - 12.