Undefined is not a function error formatting date in JS

Question

I got an undefiend error passing my date value into formatDate function, why? How to ceate an instance in my case?

    function formatDate(date) {
        if (date) {
            var hours = date.getHours();
            var minutes = date.getMinutes();
            var format = hours < 12 ? 'am' : 'pm';
            hours = hours % 12;
            hours = hours ? hours : 12; // making 0 a 12
            minutes = minutes < 10 ? '0' + minutes : minutes;
            var time = hours + ':' + minutes + ' ' + format;
            var output = date.getMonth() + 1 + "/" + date.getDate() + "/" + date.getFullYear() + " " + time;

            console.log(output);
          alert(output);

        }
    }

    <input type="datetime-local" onblur="formatDate(this.value)" />

Victor · Accepted Answer · 2015-01-03 03:10:55Z

2

It's because the date that you receive in your function is a string from your input, not a Date object.

So before you call something like date.getHours(); you must need to parse your date as string to Date or you will have the Uncaught TypeError: undefined is not a function error.

answered Jan 3, 2015 at 3:10

Victor

5,1513 gold badges44 silver badges58 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

rvighne Over a year ago

And to parse the date as a string, you would do new Date()

Collectives™ on Stack Overflow

Undefined is not a function error formatting date in JS

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related