Is there a way to pass a list of JSON objects from JS to C#?

Question

Something I'm confusing. The Javascript is going to produce the following JSON data.

{type:"book"     , author: "Lian", Publisher: "ABC"}
{type:"Newspaper", author: "Noke"}

This is only an example, actually I've got more than this.

Since I have common fields between different JSON data, so I don't know is it possible to pass this to C# at one time. What I want to do is pass this to c# then do some processing, what is the best way to do? I'm using ASP.NET MVC2.

Thanks for your answer or hints.

Answer 1

The combination of the 2 JSON statements above are, together, not valid JSON. That being said, you will not be able to use the JavaScriptSerializer class to deserialize that data into c# structure directly. Instead you will have to do some manual parsing first, to either break it down into valid JSON or just do full on manual parsing.

What I would actually recommend is sending over valid JSON instead. You can accomplish this by doing something like this:

{list: [
    {type:"book"     , author: "Lian", Publisher: "ABC"},
    {type:"Newspaper", author: "Noke"} ]

Hard to say exactly, since only you know the details of your use case. You can send this data over using a traditional 'ajax' request. This is very easy to do with out any of the many JS libraries out there, but I would recommend just going with one anyway - they offer higher level constructs that are easier to use (and address cross-browser idiosyncrasies).

Since you are using ASP.NET MVC2, I would recommend jQuery. Microsoft is now backing jQuery as their JS library of choice and even make it default for new web projects.

Once you pass the above JSON to C#, you can deserialize it by doing something like this:

JavaScriptSerializer serializer = new JavaScriptSerializer();
var result = serialzer.Deserialize<Dictionary<string, object>>(postedJSONData);

Your result will then have a structure that looks like this, in C#:

Dictionary<string, object> result =>
    { "list" => object },
                object => List<object>,
                          List<object> => Dictionary<string, object>
                                          { "type" => "book", "author" => "Lian" } // etc

Answer 2

[
    {type:"book"     , author: "Lian", Publisher: "ABC"},
    {type:"Newspaper", author: "Noke"}
]

Is still valid JSON (well actually keys need to be enclosed in " as well), so you can .push() into an array each time you create a JSON record.

var list = [];
// code doing other stuff
list.push({type:"book"     , author: "Lian", Publisher: "ABC"});
// more code doing other stuff
list.push({type:"Newspaper", author: "Noke"})

Once your JSON list is constructed, you can send that list to the backend in one go.

Answer 3

You can also use the JavaScriptSerializer to deserialize your own custom type. Esentially you make a very simple type with all the properties of your json objects then call

JavaScriptSerializer serializer = new JavaScriptSerializer();
MyType result = serialzer.Deserialize<MyType>(JsonData);

You can also deserialize an array

MyType[] result = serialzer.Deserialize<MyType[]>(JsonData);