Javascript无效的日期为字符串格式

Question

I'm trying to parse time which is retrieved from MySql via jSon

something like:

new Date('12:15:24').toString('h:mmtt');

but I keep getting Invalid Date in console

What I need to do is convert 24 hour format into 12 hour am/pm and vice versa

Answer 1

The Date() constructor only likes a very restricted set of date formats. If your input format is fixed at 'hh:mm:ss' it is probably easier to format it using a simple string replace:

 function formatTime(time) { return time.replace(/(\\d?\\d)(:\\d\\d):(\\d\\d)/, function(_, h, m) { return (h > 12 ? h-12 : +h === 0 ? "12" : +h) + m + (h >= 12 ? "pm" : "am"); }); } console.log( formatTime('00:15:24') ); console.log( formatTime('09:15:24') ); console.log( formatTime('10:15:24') ); console.log( formatTime('11:15:24') ); console.log( formatTime('12:15:24') ); console.log( formatTime('13:15:24') ); console.log( formatTime('14:15:24') ); 

Further reading:

• String .replace() method
• Regular expressions
• Unary plus operator

Answer 2

I would consider using date/time manipulation library, such as http://momentjs.com/ .

You can also achieve what you want by splitting the time string and creating a Date() object. Example:

var time = '12:15:24';
var timePortions = time.split(':');
new Date(0,0,0,timePortions[0], timePortions[1], timePortions[2])

This is not a safe way to manipulate date/time, though.

Answer 3

it is better to use moment.js to handle datetime like this

 // get hours:minutes:seconds of the date 31-Jan_2016 9.31.21 console.log(moment('2016-01-31 09:30:21').format('HH:mm:ss')) // get current hours:minutes:seconds console.log(moment().format('HH:mm:ss')) // get current date-month-year hours:minutes:seconds console.log(moment('2016-01-31 09:30:21').format('DD-MM-YYYY HH:mm:ss')) 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.15.1/moment.min.js"></script>