Need help to resolve the issue when converting epoch date to human readable format - Javascript

Question

My java script application uses .net web service to get the data from back end. Everything works fine except for date / time conversion. I need to convert the epoch date returned by service to user's local browser date.

The web service returns date in the below format,

/Date(1335341422660-0500)/ 

This is what I have done to convert this to human readable date,

I strip out everything after hyphen (-) and use the remaining data for date conversion

var dateVal=dateField.replace(/-.*\)/g,')');                           
var date = new Date(parseFloat(dateVal.substr(6)));


   var dateArray=date.toString().split(" ");
   if(dateArray.length>3){
  timeZone=("("+dateArray[4])+")"
    }

 var month=date.getMonth() + 1;
 var year=date.getFullYear();
 var date=date.getDate();
 var hours= date.getHours();
 var offset=date.getTimezoneOffset();
 var finalDateStr=(year+"-"+month+"-"+dateValue)+" "+hours+":"+
                            minutes+":"+seconds+" "+timeZone;

For the above epoch value, expected date is,

4/24/2012 9:10:22 PM - This date is displayed in a .net application which is actually the source application that inserts this date in to MS SQL server whenever a new item is created / updated. They convert the SQL server date to local date (using .net) and display it in UI.

but when I form the date using the above script I am getting the value as,

2012-4-25 4:10:22 (EDT) (7 hours more compared to above date).

I am not sure where I am wrong.. Can some one help me figure out this issue?

Answer 1

Not sure if this is a great way to fix this issue...

This is what I did and seems to work fine... Again I dont think this is a fool proof solution but I checked in various time zones (with / without daylight saving time) and it seems to work......

 var dateVal=dateField.replace(/-.*\)/g,')');                           
                            var date = new Date(parseFloat(dateVal.substr(6)));

                            var dateArray=date.toString().split(" ");
                            var timeZone="(Local Time)";
                            if(dateArray.length>3){
                                timeZone=("("+dateArray[4])+")"
                            }
var date2=dateField.split("-");
                     var dateOffset=(date2[1].toString().replace(")","").replace("/",""));

if( date.toString().toUpperCase().indexOf("DT")!==-1){                        
 date.setHours(date.getHours()-(parseFloat(parseFloat(dateOffset).toString().replace(/0*$/, ''))+2));
}else{
 date.setHours(date.getHours()-(parseFloat(parseFloat(dateOffset).toString().replace(/0*$/, ''))+1));
}


                            var month=date.getMonth() + 1;
                            var year=date.getFullYear();
                            var dateValue=date.getDate();
                            var hours= date.getHours();                              
                            var minutes= date.getMinutes();
                            var seconds=date.getSeconds()
                            var finalDateStr=(year+"-"+month+"-"+dateValue)+" "+hours+":"+
                            minutes+":"+seconds+" "+timeZone;

Answer 2

For such date manipulations, you might want to consider using Moment.js.