Newtonsoft.json: Deserialization of DateTimeOffset value fails depending on system's timezone

[Advanium]

I encountered an issue while materializing a date/time value as DateTimeOffset.
Please see https://stackoverflow.com/questions/50628374 where I initially asked for help.

Source/destination types

public class RootObject
{
    [JsonProperty("revisedDate", NullValueHandling = NullValueHandling.Ignore)]
    public DateTimeOffset? RevisedDate { get; set; }
}

Source/destination JSON

{
  "revisedDate": "0001-01-01T00:00:00"
}

Expected behavior

In the abscence of a timezone, I expected Json.NET to in this case deserialize the value and return a valid DateTimeOffset equal to DateTimeOffset.MinValue.

Actual behavior

An exception was thrown in the DateTimeOffset.Parse method, and Json.NET reported "Could not convert string to DateTimeOffset: 0001-01-01T00:00:00. Path 'resource.revisedDate', line 20, position 44." to the caller.

Steps to reproduce

Please refer to the answer provided by dbc for steps to reproduce the issue:
https://stackoverflow.com/a/50631270/1503584

[zongbingwang]

I also met this issue

[vuphuctho]

Looking for solution to this issue too.

[modmoto]

Having the same issue, the workaround seems really hacky in my opinion :/

[PVLopes]

Also having this problem with an android app using xamarin.
It was a pain to find out the problem, cause i'm in UTC+0, while the clients are in UTC+n

[netbidev]

Thanks a lot for solution!

[Kalroth]

This issue isn't limited to Json.NET, Microsoft's System.Text.Json does also raise an exception.

This is because DateTimeOffset values are converted to UTC internally, and when the value "0001-01-01T00:00:00" is deserialized to DateTimeOffset, it will use the local timezone. When your timezone offset is positive, it results in the value "0001-01-01T00:00:00+01:00" which is less than DateTimeOffset.MinValue when converted to UTC and thus an invalid DateTimeOffset value.

https://docs.microsoft.com/en-us/dotnet/api/system.datetimeoffset.minvalue:

Any DateTimeOffset value is converted to Coordinated Universal Time (UTC) before the method performs the comparison with MinValue. This means that a DateTimeOffset value whose date and time are close to the minimum range, but whose offset is positive, may throw an exception. For example, the value 1/1/0001 1:00:00 AM +02:00 is out of range because it is one hour earlier than MinValue when it is converted to UTC.

I have found no fix for this other than to write a custom (and complex) JsonConverter to handle the invalid DateTimeOffset values.

[alecjames]

I also have this issue. (Thanks for the explanation and work around)

[sinand99]

+1
this needs to be solved to avoid ugly hacks