不能让MVC4的WebAPI包括JSON空字段 [英] Can't make MVC4 WebApi include null fields in JSON
问题描述
我试图序列化对象作为JSON与MVC4的WebAPI（RTM - 刚刚安装VS2012 RTM，但今天是昨天中具有RC这个问题），我想对在JSON输出中呈现的所有空值。
像这样的：
I'm trying to serialize objects as JSON with MVC4 WebAPI (RTM - just installed VS2012 RTM today but was having this problem yesterday in the RC) and I'd like for all nulls to be rendered in the JSON output. Like this:
[{"Id": 1, "PropertyThatMightBeNull": null},{"Id":2, "PropertyThatMightBeNull": null}]
但即时得到为
[{"Id":1},{"Id":2}]
我发现这个Q / A 的WebAPI犯规序列化空字段但回答都对我不起作用，或者我没有把握放在哪里了答案。
I've found this Q/A WebApi doesnt serialize null fields but the answer either doesn't work for me or I'm failing to grasp where to put the answer.
下面是我已经试过：
-
在Global.asax.cs中的的Application_Start，我说：
In Global.asax.cs's Application_Start, I added:
var json = GlobalConfiguration.Configuration.Formatters.JsonFormatter;
json.SerializerSettings.NullValueHandling = Newtonsoft.Json.NullValueHandling.Include;
json.SerializerSettings.DefaultValueHandling = Newtonsoft.Json.DefaultValueHandling.Include;
这不（似乎）的错误，似乎基于望着我试了下东西实际执行。
This doesn't (seem to) error and seems to actually execute based on looking at the next thing I tried.
在控制器方法（在ApiController的子类），又说：
In a controller method (in a subclass of ApiController), added:
base.Configuration.Formatters.JsonFormatter.SerializerSettings.NullValueHandling = Newtonsoft.Json.NullValueHandling.Include;
base.Configuration.Formatters.JsonFormatter.SerializerSettings.DefaultValueHandling = Newtonsoft.Json.DefaultValueHandling.Include;
我说的＃1执行，因为在＃2这两个值都已经设置之前，这些线路跑了作为我踩通过。
I say #1 executed because both values in #2 were already set before those lines ran as I stepped through.
在一个绝望的举动（因为我真的不想装饰每个对象的每一个属性）我尝试添加该ATTRIB到为空和无属性：
In a desperation move (because I REALLY don't want to decorate every property of every object) I tried adding this attrib to a property that was null and absent:
[JsonProperty(DefaultValueHandling = DefaultValueHandling.Include,
NullValueHandling = NullValueHandling.Include)]
这三个产生相同的JSON与空属性省略。
All three produce the same JSON with null properties omitted.
其他注意事项：
- 在IIS本地运行（试过建于太），Windows 7的RTM VS2012
- 控制器方法返回列表 - 尝试过的IEnumerable
- 我想序列化的对象是波苏斯。
推荐答案
我终于碰上了这个<一个href=\"http://forums.asp.net/t/1824580.aspx/1?Serializing+to+JSON+Nullable+Date+gets+ommitted+using+Json+NET+and+Web+API+despite+specifying+NullValueHandling\" rel=\"nofollow\">http://forums.asp.net/t/1824580.aspx/1?Serializing+to+JSON+Nullable+Date+gets+ommitted+using+Json+NET+and+Web+API+despite+specifying+NullValueHandling它描述了我的经历作为固定的RTM在测试中的错误。
I finally came across this http://forums.asp.net/t/1824580.aspx/1?Serializing+to+JSON+Nullable+Date+gets+ommitted+using+Json+NET+and+Web+API+despite+specifying+NullValueHandling which describes what I was experiencing as a bug in the beta that was fixed for the RTM.
虽然我已经安装了VS2012 RTM，我的项目仍在使用所有的测试就用的NuGet包。所以我nugetted（nugot？）更新的一切，一切都很好，现在（用1号从我的问题）。虽然我感觉傻有烧半天。
Though I had installed VS2012 RTM, my project was still using all the nuget packages that the beta came with. So I nugetted (nugot?) updates for everything and all is now well (using #1 from my question). Though I'm feeling silly for having burned half a day.
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