Parsing JSON DateTime from Newtonsoft's JSON S

Question

I've serialized an object using Newtonsoft's JSON serializer, and the DateTime has come through as:

/Date(1237588418563+0000)/

When I $.evalJSON() on that, it is an object but I can't find any normal Date methods like toUTCString on it.

Any ideas what I can do with this?

Answer 1

The JSON object contained something like this:

var data = {"CreatedDate":"/Date(1327572000000-1000)/"});

 ///
var oddDateTimeZone = data.CreatedDate;
var utcDateTime = oddDateTimeZone.substr(oddDateTimeZone.indexOf("(")+1, 13);
var utcZone = oddDateTimeZone.substr(oddDateTimeZone.indexOf("-")+1, 4);
var utcDateTimeZone = new Date(Number(utcDateTime)-(Number(utcZone)));

but, still it would be better to fix the JSON object so the date function fired without using something like eval() or window[]. Maybe in jQuery. Not sure.

Don't forget that the offset could be + and not just - for the offset!

Answer 2

Use one of the JsonConverters that come with Json.NET for working with dates to get a better format. JavaScriptDateTimeConverter will automatically give you a JavaScript date.

public class LogEntry    
{    
  public string Details { get; set; }    
  public DateTime LogDate { get; set; }
}

[Test]
public void WriteJsonDates()
{    
  LogEntry entry = new LogEntry    
  {    
    LogDate = new DateTime(2009, 2, 15, 0, 0, 0, DateTimeKind.Utc),    
    Details = "Application started."    
  };    


  string defaultJson = JsonConvert.SerializeObject(entry);    
  // {"Details":"Application started.","LogDate":"\/Date(1234656000000)\/"}     

  string javascriptJson = JsonConvert.SerializeObject(entry, new JavaScriptDateTimeConverter());    
  // {"Details":"Application started.","LogDate":new Date(1234656000000)}

  string isoJson = JsonConvert.SerializeObject(entry, new IsoDateTimeConverter());    
  // {"Details":"Application started.","LogDate":"2009-02-15T00:00:00Z"}    
}

Documentation: Serializing Dates in JSON with Json.NET

Answer 3

As of Newtonsoft Json.Net version 4.5r5 you use the JsonPropertyAttribute Class class and set its ItemConverterType Property property. Usage:

// class to be serialized
public class MyClass
{
    [JsonProperty(ItemConverterType = typeof(JavaScriptDateTimeConverter))]
    public DateTime? DateTime1;
    public DateTime? DateTime2;
}

As I have observed this will set the DateTimeConverter for all properties in this class not just the one before which is declared.

Answer 4

ObjectMapper mapper = new ObjectMapper();

mapper.registerModule(new JavaTimeModule());

mapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);

This works for me

Answer 5

I came up with a different approach which might be useful to some. Basically I create my own CustomDateConverter that I call when I need it. The converter takes 2 parameters, a date format e.g. yyyy-MM-dd HH:mm:ss and a TimeZoneInfo, which allows me to convert the date from UTC to the user's time zone:

public class JSONCustomDateConverter : DateTimeConverterBase
{
    private TimeZoneInfo _timeZoneInfo;
    private string _dateFormat;

    public JSONCustomDateConverter(string dateFormat, TimeZoneInfo timeZoneInfo)
    {
        _dateFormat = dateFormat;
        _timeZoneInfo = timeZoneInfo;
    }
    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(DateTime);
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        throw new NotImplementedException();
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        writer.WriteValue(TimeZoneInfo.ConvertTimeFromUtc(Convert.ToDateTime(value), _timeZoneInfo).ToString(_dateFormat));
        writer.Flush();
    }

You can use it like this:

 var jsonString = JsonConvert.SerializeObject(myObject, Formatting.None, new JsonSerializerSettings { NullValueHandling = NullValueHandling.Ignore, Converters = new List<JsonConverter>() { new JSONCustomDateConverter("yyyy-MM-dd HH:mm:ss", loggedUser.Timezone) } });

Obviously you could remove anything related to time zone if you only want custom date formatting. Let me know it that helped!

Answer 6

Ran into the same problem, and found a solution based on the link from Adam:

new Date(yourDate.substr(yourDate.indexOf("(") + 1, 13) - 0));

It looks like a Unix timestamp, which javascript is easily able to convert into a date object. The - 0 is simply to make javascript treat the substr output as an integer... I guess you could Number() it as well, if you don't like the looks of - 0