Converting .NET DateTime to JSON

> Possible Duplicate:
> How to format a JSON date?

My webs service is returning a DateTime to a jQuery call. The service returns the data in this format:

/Date(1245398693390)/

How can I convert this into a JavaScript-friendly date?

What is returned is milliseconds since epoch. You could do:

var d = new Date();
d.setTime(1245398693390);
document.write(d);

On how to format the date exactly as you want, see full Date reference at http://www.w3schools.com/jsref/jsref_obj_date.asp

You could strip the non-digits by either parsing the integer (as suggested here):

var date = new Date(parseInt(jsonDate.substr(6)));

Or applying the following regular expression (from Tominator in the comments):

var jsonDate = jqueryCall();  // returns "/Date(1245398693390)/"; 
var re = /-?\d+/; 
var m = re.exec(jsonDate); 
var d = new Date(parseInt(m[0]));

I have been using this method for a while:

using System;

public static class ExtensionMethods {
  // returns the number of milliseconds since Jan 1, 1970 (useful for converting C# dates to JS dates)
  public static double UnixTicks(this DateTime dt)
  {
    DateTime d1 = new DateTime(1970, 1, 1);
    DateTime d2 = dt.ToUniversalTime();
    TimeSpan ts = new TimeSpan(d2.Ticks - d1.Ticks);
    return ts.TotalMilliseconds;
  }
}

Assuming you are developing against .NET 3.5, it's a straight copy/paste. You can otherwise port it.

You can encapsulate this in a JSON object, or simply write it to the response stream.

On the Javascript/JSON side, you convert this to a date by simply passing the ticks into a new Date object:

jQuery.ajax({
  ...
  success: function(msg) {
    var d = new Date(msg);
  }
}

To parse the date string using String.replace with backreference:

var milli = "/Date(1245398693390)/".replace(/\/Date\((-?\d+)\)\//, '$1');
var d = new Date(parseInt(milli));

If you pass a DateTime from a .Net code to a javascript code, C#:

DateTime net_datetime = DateTime.Now;

javascript treats it as a string, like "/Date(1245398693390)/":

You can convert it as fllowing:

// convert the string to date correctly
var d = eval(net_datetime.slice(1, -1))

or:

// convert the string to date correctly
var d = eval("/Date(1245398693390)/".slice(1, -1))

If you're having trouble getting to the time information, you can try something like this:

	d.date = d.date.replace('/Date(', '');
	d.date = d.date.replace(')/', '');	
	var expDate = new Date(parseInt(d.date));

the conversion from 1970,1,1 needs the double rounded to zero decimal places i thinks

DateTime d1 = new DateTime(1970, 1, 1);
DateTime d2 = dt.ToUniversalTime();
TimeSpan ts = new TimeSpan(d2.Ticks - d1.Ticks);
return Math.Round( ts.TotalMilliseconds,0);

on the client side i use

new Date(+data.replace(/\D/g, ''));

http://stevenlevithan.com/assets/misc/date.format.js

var date = eval(data.Data.Entity.Slrq.replace(/\/Date\((\d )\)\//gi, "new Date($1)"));  
alert(date.format("yyyy-MM-dd HH:mm:ss"));  
alert(dateFormat(date, "yyyy-MM-dd HH:mm:ss"));  

You can try a 3rd party library like json.net There's documention on the project site. It does say it requires .net 3.5.

Otherwise there's another one called Nii.json which i believe is a port from java. I found a link to it on this blog

The previous answers all state that you can do the following:

var d = eval(net_datetime.slice(1, -1));

However, this doesn't work in either Chrome or FF because what's getting evaluated literally is:

// returns the current timestamp instead of the specified epoch timestamp
var d = Date([epoch timestamp]);

The correct way to do this is:

var d = eval("new " + net_datetime.slice(1, -1)); // which parses to

var d = new Date([epoch timestamp]); 

Thought i'd add my solution that i've been using.

If you're using the System.Web.Script.Serialization.JavaScriptSerializer() then the time returned isn't going to be specific to your timezone. To fix this you'll also want to use dte.getTimezoneOffset() to get it back to your correct time.

String.prototype.toDateFromAspNet = function() {
    var dte = eval("new " + this.replace(/\//g, '') + ";");
    dte.setMinutes(dte.getMinutes() - dte.getTimezoneOffset());
    return dte;
}

now you'll just call

"/Date(1245398693390)/".toDateFromAspNet();

> Fri Jun 19 2009 00:04:53 GMT-0400 (Eastern Daylight Time) {}