如何以JSON格式传递TimeSpan值？

Question

I use Fiddler to test my WCF Rest. I always get

HTTP/1.1 400 Bad Request  

with this post value:

{
    "session":{
        "Session":"088a688d-ea69-4264-9266-381e9e540d00",
        "LoginID":"testid",
        "Serial":"testserial"
    },
    "sub":[
        {
            "Type":0,
            "StartDate":"\/Date(1319731200000+0800)\/",
            "EndDate":"\/Date(1319731200000+0800)\/",
            "Duration":"12:12:12"
        }
    ]
}  

I get the error in 'Duration' value. I've been searching on net but no luck at all.
I hope I'll find the answer here. Thanks a lot!

Answer 1

The simple approach is to parse the timespan as a string and converting to a TimeSpan using its static 'parse' routine.

With JSON and WCF you are relying on the JSON Serialiser to convert objects back and forth, unfortunately once you start 'moving' away from native object types, ie strings, numerics, and into specific object, it tends to choke unless you use the exact format.

Personally, I've had no experience of passing Timespan's through the DataContractJsonSerializer what format is required, however this post will highlight the exact format along with whether it is possible

Answer 2

What is the .NET type of "sub"? It looks like a collection or array type of some sort; what is the type that .NET expects those elements to have? Does that type have the properties Type, StartDate, EndDate, and Duration? Does it have any other properties that are marked with [IsRequiredAttribute] but not present?

If you craft up a fresh DataContractJsonSerializer (type = TimeSpan), and try to deserialize just the string "12:12:12", what happens then?

I am not giving you an answer yet -- but I think doing these exercises should not solve your problem now, but it will also help diagnose future errors you may encounter in the deserialization of this string.

See also Deserialize array values to .NET properties using DataContractJsonSerializer for some pointers