Javascript DateFormat for different timezones

Question

I\'m a Java developer and I\'m used to the SimpleDateFormat class that allows me to format any date to any format by settings a timezone.

Date date = new Dat         


        

Answer 1

Since my requirement was a typescript solution but I stumbled here I used this answer to write my typescript function.

Based on answer above, a function in typescript which converts a timestamp or a date object into a formatted local time string.

const formatDateString = (date_or_ts:Date|number):string=>{
    let obj:Date;

    if(typeof date_or_ts === "number"){
        obj = new Date(date_or_ts*1000);
        // obj=new Date(obj.getTime()+obj.getTimezoneOffset()*60000+timezone*3600000);
    }else{
        obj = date_or_ts;
    }
    const format = "dd-MM-yyyy hh:mm:ss";
    let two=function(s:number){
        return s<10?"0"+s:s+"";
    }
    return format.replace(/dd|MM|yyyy|hh|mm|ss/g, function(pattern){
        const months = ["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"];
        switch(pattern){
            case "dd" : return two(obj.getDate()).toString();
            case "MM" : return months[obj.getMonth()];
            case "yyyy" : return obj.getFullYear().toString();
            case "hh" : return two(obj.getHours()).toString();
            case "mm" : return two(obj.getMinutes()).toString();
            case "ss" : return two(obj.getSeconds()).toString();
            default: return "";
        }
    });
}

Answer 2

This is an old question, but since I found it:

As mentioned, there's nothing reasonable built-in.

As for libs, there is Moment Timezone for Moment.js.

Here is a JSfiddle with an example: http://jsfiddle.net/kunycrkb/

The same code inline:

var m = moment("2014-06-01T13:05:00Z");
var f = "HH:mm z";

$("#results").text(m.tz("UTC").format(f) + " is " + m.tz("EST").format(f) +  "!");

Answer 3

JavaScript does not have build in support for other time zone than the local one. You can only express a date in local time or in UTC time. There is no way to change the time zone offset of a Date object.

Thus, there is no "neat" way to solve your problem.

Answer 4

Don't write your own stuff; just get datejs: http://www.datejs.com/

You can figure out what the timezone offset is set to in the execution environment like this:

var local = new Date();
var utc = Date.UTC(local.getFullYear(), local.getMonth(), local.getDate(), local.getHours(), local.getMinutes(), local.getSeconds(), local.getMilliseconds());
var tz = (utc - local.getTime()) / (60 * 60 * 1000);

Answer 5

Attempting to (ever so slightly) improve upon mwilcox's suggestion:

Date.prototype.format = function(format, tzAdjust) {

    // get/setup a per-date-instance tzDate object store
    var tzCache = this.__tzCache = this.__tzCache || (this.__tzCache = {});

    // fetch pre-defined date from cache 
    var tzDate = tzCache[tzAdjust];
    if ( !tzDate )
    {
      // on miss - then create a new tzDate and cache it
      tzDate = tzCache[tzAdjust] = new Date( this );
      // adjust by tzAdjust (assuming it's in minutes 
      // to handle those weird half-hour TZs :) 
      tzDate.setUTCMinutes( tzDate.getUTCMinutes()+tzAdjust );
    }

    return format.replace(/dd|MM|yyyy|hh|mm|ss/g, function(pattern){
               // replace each format tokens with a value 
               // based on tzDate's corresponding UTC property
             });
}

Answer 6

The ISO Extended format for common date is YYYY-MM-DD, and for time is hh:mm:ss. Either format can be understood, unambiguously, worldwide.

See also: http://jibbering.com/faq/#dates