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iosswiftnsdatensregularexpression

How to check for valid time format?

I am trying to check if a string variable conforms to either hh:mm AM or hh:mm PM twelve hour time format. Where hh represents hours, mm represents minutes and AM or PM represents morning or evening. I have a CSV file where each line contains a time in 12-hour format for instance 01:00 PM or 12:00 AM. I am extracting each line and checking if it conforms to the desired format.

Solution

  • Just pass the string to a date formatter with the required format. If it returns a Date object, then the string contains valid date.

    func getDate(from string: String) -> Date? {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "yyyy-MM-dd h:mm a"
    return dateFormatter.date(from: string)
}

if let date = getDate(from: "2019-02-14 9:28 PM") {
    print(date)
}

    Check NSDateFormatter.com for reference.