在常规的.net中,
如果我们有一个DateTimeKind.Unspecified的时间
如果我们转换ToLocal – 它假定转换时输入日期是UTC.
如果我们转换为ToUniversal – 它假定转换时输入日期是本地的
如果我们有一个DateTimeKind.Unspecified的时间
如果我们转换ToLocal – 它假定转换时输入日期是UTC.
如果我们转换为ToUniversal – 它假定转换时输入日期是本地的
但是,在JSON.Net中,如果我们在JSON.Net中的字符串日期未指定,它似乎没有这个逻辑?看看我下面的测试用例 – 我做错了吗?或者这是设计?或JSON.Net中的错误?
谢谢!
- // TODO: This Fails with output
- // date string: "2014-06-02T21:00:00.0000000"
- // date serialized: 2014-06-02T21:00:00.0000000Z
- // Expected date and time to be <2014-06-03 04:00:00>,but found <2014-06-02 21:00:00>.
- [TestMethod]
- public void NEW_Should_deserialize_unspecified_datestring_to_utc_date()
- {
- string dateString = "\"2014-06-02T21:00:00.0000000\"";
- DateTime dateRaw = new DateTime(2014,6,2,21,DateTimeKind.Unspecified);
- DateTime dateRawAsUtc = new DateTime(2014,3,4,DateTimeKind.Utc);
- dateRawAsUtc.Should().Be(dateRaw.ToUniversalTime());
- JsonSerializerSettings settings = new JsonSerializerSettings();
- settings.DateTimeZoneHandling = DateTimeZoneHandling.Utc;
- settings.DateFormatHandling = DateFormatHandling.IsoDateFormat;
- DateTime dateSerialized = JsonConvert.DeserializeObject<DateTime>(dateString,settings);
- Console.WriteLine("date string: " + dateString);
- Console.WriteLine("date serialized: " + dateSerialized.ToString("o"));
- dateSerialized.Kind.Should().Be(DateTimeKind.Utc);
- dateSerialized.Should().Be(dateRaw.ToUniversalTime());
- dateSerialized.Should().Be(dateRawAsUtc);
- }
- // TODO: This Fails with output
- // date string: "2014-06-02T21:00:00.0000000"
- // date serialized: 2014-06-02T21:00:00.0000000-07:00
- // Expected date and time to be <2014-06-02 14:00:00>,but found <2014-06-02 21:00:00>.
- [TestMethod]
- public void NEW_Should_deserialize_unspecified_datestring_to_local_date()
- {
- string dateString = "\"2014-06-02T21:00:00.0000000\"";
- DateTime dateRaw = new DateTime(2014,DateTimeKind.Unspecified);
- DateTime dateRawAsLocal = new DateTime(2014,14,DateTimeKind.Local);
- dateRawAsLocal.Should().Be(dateRaw.ToLocalTime());
- JsonSerializerSettings settings = new JsonSerializerSettings();
- settings.DateTimeZoneHandling = DateTimeZoneHandling.Local;
- settings.DateFormatHandling = DateFormatHandling.IsoDateFormat;
- DateTime dateSerialized = JsonConvert.DeserializeObject<DateTime>(dateString,settings);
- Console.WriteLine("date string: " + dateString);
- Console.WriteLine("date serialized: " + dateSerialized.ToString("o"));
- dateSerialized.Kind.Should().Be(DateTimeKind.Local);
- dateSerialized.Should().Be(dateRaw.ToLocalTime());
- dateSerialized.Should().Be(dateRawAsLocal);
- }
- [TestMethod]
- public void NEW_Should_deserialize_unspecified_datestring_to_unspecified_date()
- {
- string dateString = "\"2014-06-02T21:00:00.0000000\""; // unspecified,does not have the 'Z'
- DateTime dateRaw = new DateTime(2014,DateTimeKind.Unspecified);
- JsonSerializerSettings settings = new JsonSerializerSettings();
- settings.DateTimeZoneHandling = DateTimeZoneHandling.Unspecified;
- settings.DateFormatHandling = DateFormatHandling.IsoDateFormat;
- DateTime dateSerialized = JsonConvert.DeserializeObject<DateTime>(dateString,settings);
- Console.WriteLine("date string: " + dateString);
- Console.WriteLine("date serialized: " + dateSerialized.ToString("o"));
- dateSerialized.Kind.Should().Be(DateTimeKind.Unspecified);
- dateSerialized.Should().Be(dateRaw);
- }
解决方法
我不是百分百肯定你在这里寻找什么,但我认为假设JSON.Net在没有一点帮助的情况下满足你的所有需求是不安全的.如
Mr. Newton says:
Dates in JSON are hard.
首先要确定是否要支持接受未指定的日期,或者是否要假设所有传入的日期都是通用的,即使它们缺少尾随的Z.
如果您假设所有传入日期都是通用的,您可以看看它们是否有尾随Z,如果没有,则添加它(不完全是生产代码,但您明白了):
- if (!dateString.EndsWith("Z\"",StringComparison.InvariantCultureIgnoreCase))
- {
- dateString = dateString.Substring(0,dateString.LastIndexOf("\"",StringComparison.InvariantCultureIgnoreCase)) + "Z\"";
- }
假设的这种变化确实要求将您测试的日期修改为Utc.
如果您不想假定传入日期是通用的,而是将它们视为未指定,则需要通过替换来更改转换传入JSON的方式:
- JsonSerializerSettings settings = new JsonSerializerSettings();
- settings.DateTimeZoneHandling = DateTimeZoneHandling.Utc;
- settings.DateFormatHandling = DateFormatHandling.IsoDateFormat;
- DateTime dateSerialized = JsonConvert.DeserializeObject<DateTime>(dateString,settings);
有:
- var oConverter = new Newtonsoft.Json.Converters.IsoDateTimeConverter();
- DateTime dateSerialized = JsonConvert.DeserializeObject<DateTime>(dateString,oConverter);
这将导致一个未指定的日期与dateString完全匹配.这是你的助手发挥作用的地方:
- if (dateSerialized.Kind == DateTimeKind.Unspecified)
- {
- dateSerialized = dateSerialized.ToUniversalTime();
- }
这意味着完整的,修订的第一个测试将如下所示,它将通过:
- string dateString = "\"2014-06-02T21:00:00.0000000\"";
- DateTime dateRaw = new DateTime(2014,DateTimeKind.Unspecified);
- DateTime dateRawAsUtc = new DateTime(2014,DateTimeKind.Utc);
- dateRawAsUtc.Should().Be(dateRaw.ToUniversalTime());
- var oConverter = new Newtonsoft.Json.Converters.IsoDateTimeConverter();
- DateTime dateSerialized = JsonConvert.DeserializeObject<DateTime>(dateString,oConverter);
- if (dateSerialized.Kind == DateTimeKind.Unspecified)
- {
- dateSerialized = dateSerialized.ToUniversalTime();
- }
- Console.WriteLine("date string: " + dateString);
- Console.WriteLine("date serialized: " + dateSerialized.ToString("o"));
- dateSerialized.Kind.Should().Be(DateTimeKind.Utc);
- dateSerialized.Should().Be(dateRaw.ToUniversalTime());
- dateSerialized.Should().Be(dateRawAsUtc);