How can I determine if a user has included a time in a single input/string?

Question

I'm asking the user to type a meeting description in one field. I'd like to intelligently guess/parse when a user includes a time in this input, to save them from having to fill out a separate time input field.

Google Calendar uses this kind of parsing to pre-fill time fields.

Example inputs:

• Meet at Burger King at 2:30 - I want to pull out "2:30" and convert it to a date/time
• Denny's 2pm - I want to pull out "2pm"
• 1 at McDonald's - I want to pull out "1"

I'd be grateful for any help!

Answer 1

I know you are asking for a JS solution, but I wrote some code in PHP that you might want to check and see if the logic helps you with your project.

<?php
$string1 = "Meet at Burger King at 2:30";
$string2 = "Denny's 2pm";
$string3 = "I want to buy 2 phones at 1";

print iterateString($string1).  "- It should return 2:30<br>";
print iterateString($string2). "- It should return 2pm<br>";
print iterateString($string3). "- It should return 1:00<br>";

function isTime($date, $formats=array("H:i","G:i","Ha","ha", "Ga", "ga")) {
    foreach($formats as $format) {
        $d = DateTime::createFromFormat($format, $date);
        $fd = $d ? $d->format($format) : false;

        if ($d && $fd == $date) {
            return $fd;
        }
    }
    return false;
}

function iterateString($string) {
    $singleTime = false;
    $words =  explode(" ",$string);
    foreach($words as $word) {
        if ($singleTime && ctype_digit($word)) {
            $word = $word . ":00";
        }

        if($time = isTime($word)) {
            return $time;
        }

        if($word == 'at') {
            $singleTime = true;
        } else {
            $singleTime = false;
        }
    }
    return "error";
}