Bug 20457 - System.Xml : Rare parse issue in System.DateTime
Summary: System.Xml : Rare parse issue in System.DateTime
Alias: None
Product: Class Libraries
Classification: Mono
Component: System.XML ()
Version: 3.4.0
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2014-06-07 14:21 UTC by Eirik Tsarpalis
Modified: 2014-07-04 12:04 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Eirik Tsarpalis 2014-06-07 14:21:56 UTC
This is an extremely rare case in which in which DateTime parsing yields a wrong date. The XmlConvert methods are marked as deprecated, however these are still used by the XmlWriter/Reader classes.

Reproducing code in F#

#r "System.Xml"

open System
open System.Xml

let date1 = DateTime(634682436600000000L) // March 24 2012
let date2 = date1 |> XmlConvert.ToString |> XmlConvert.ToDateTime

date1 = date2 // false
Comment 1 Marek Safar 2014-07-04 11:39:44 UTC
I am using following C# program and cannot reproduce the issue. What culture are your running

using System;
using System.Xml;
using System.Globalization;

class X
	public static void Main ()
		Console.WriteLine (CultureInfo.CurrentCulture.Name);
		var dt = new DateTime (634682436600000000L);
		var s = XmlConvert.ToString (dt);
		var dt2 = XmlConvert.ToDateTime (s);
		Console.WriteLine (dt == dt2);

Comment 2 Eirik Tsarpalis 2014-07-04 12:00:38 UTC
Hi Marek,

I'm running on "en-US". I can confirm that your C# code also reproduces this issue on my machine.
Comment 3 Marek Safar 2014-07-04 12:04:04 UTC
It works for me with en-US too but I am testing 3.6 only