Question

I have a very basic ASP MVC application exposing a static list of publications (see code and result below).

Code:

    public JsonResult Index()
    {
        List<Publication> list = new List<Publication>() {
            new Publication() { Id = 1, Name = "War and Peace" },
            new Publication() { Id = 2, Name = "Harry Potter" },
            new Publication() { Id = 3, Name = "Cat in the Hat" }
        };
        return this.Json(list, JsonRequestBehavior.AllowGet);
    }

Result:

[{“Id”:1,”Name”:”War and Peace”},{“Id”:2,”Name”:”Harry Potter”},{“Id”:3,”Name”:”Cat in the Hat”}]

When I attempt to consume it in Android I get the following error:

04-15 12:00:57.331: W/System.err(209): org.json.JSONException: A JSONObject text must begin with ‘{‘ at character 1 of [{“Id”:1,”Name”:”War and Peace”},{“Id”:2,”Name”:”Harry Potter”},{“Id”:3,”Name”:”Cat in the Hat”}]

I can remove the starting [ and ending ] and it stops the error from appearing. The other option is to put the { publications: logic at the beginning of the android code, but that seems like it should already be there.

How can I update the code in the MVC application to produce a “ready to be consumed” version of JSON?

Any help is greatly appreciated.

Answer 1

First, you shouldn’t modify your json string when received, because it may mess up with the parsing.

Second, your Json string is in array format because it starts with [ and ends with ]. So, instead of using JSONObject, you should use JSONArray.