Check the date format of string if it's according to required format or not

Just same like Java, check if it can parse properly

let dateFormatterGet = DateFormatter()
dateFormatterGet.dateFormat = "yyyy-MM-dd hh:mm:ss"
let someDate = "string date"

if dateFormatterGet.date(from: someDate) != nil {
    // valid format
} else {
    // invalid format
}

For Swift 4 the syntax have changed a bit:

 func isValidDate(dateString: String) -> Bool {
    let dateFormatterGet = DateFormatter()
    dateFormatterGet.dateFormat = "yyyy-MM-dd hh:mm:ss"
    if let _ = dateFormatterGet.date(from: dateString) {
        //date parsing succeeded, if you need to do additional logic, replace _ with some variable name i.e date
        return true
    } else {
        // Invalid date
        return false
    }
}