Json.NET Deserialize Object change the timezone to local time?

Try to use:

var content = @"{""startDateTime"":""2018-07-19T14:30:00+09:30""}";

var jss = new JsonSerializerSettings
    {
         DateFormatHandling = DateFormatHandling.IsoDateFormat,
         DateTimeZoneHandling = DateTimeZoneHandling.Local, 
         DateParseHandling = DateParseHandling.DateTimeOffset
    };

var obj = JsonConvert.Deserialize<Object>(content, jss);

If you're using WebApi you can configure it globally by adding in the WebApiConfig.cs :

config.Formatters.JsonFormatter.SerializerSettings.DateTimeZoneHandling 
= Newtonsoft.Json.DateTimeZoneHandling.Local;

This will specifically tell the JsonFormatter to include and understand the local time zone information when serializing and deserializing a date.