ASMX webservice - return JSON instead of XML

Question

I have a web service that contains one method:

[WebMethod]
public string Movies()
{
    using (var dataContext = new MovieCollectionDataContext())
    {
        var query = dataContext.Movies.Select(m =>new{m.Title,m.ReleaseDate}).Take(20);
        var serializer = new JavaScriptSerializer();
        return serializer.Serialize(query);
    }
}

The method properly serializes the object, but when I view the response in FireBug, it looks like this:

<?xml version="1.0" encoding="utf-8"?>
<string xmlns="http://tempuri.org/">[{"Title":"SQL","ReleaseDate":"\/Date(1224007200000)\/"},{"Title":"Termonator Salvation","ReleaseDate":"\/Date(1224007200000)\/"}]</string>

Here is jQuery method in which I use Kendo Data Source

$(function () {
    alert("Welcome To Kendo");
    var dataSource = new kendo.data.DataSource(
                {
                    transport: {
                        read: {
                            type: "POST",
                            dataType: "json",
                            url: "/MovieService.asmx/Movies"
                           // contentType: "application/json; charset=utf-8"

                        }
                    },
                    change: function (e) {
                        alert(e);

                    },
                    error: function (e) {
                        alert(e[2]);
                    },
                    pageSize: 10,
                    schema: {
                        data: "d"

                    }


                });

    $("#MovieGridView").kendoGrid({
        dataSource: dataSource,
        height: 250,
        scrollable: true,
        sortable: true,
        pageable: true,
        columns: [
            { field: "Title", title: "Movie Name" },
            { field: "ReleaseDate", title: "Movie Release" }
            ],
        editable: "popup",
        toolbar: ["create"]
    });
});

The above code show what I am doing in jQuery and when the error event call I got this error

SyntaxError: JSON.parse: unexpected character

How can I convert the above data into JSON so I can use it in jQuery? And where am I going wrong?

Answer 1

You need to specify the ResponseFormat of the method:

[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public string GetMovies() {
}

Note: For the sake of others who arrive at this question with similar issues, it's also important to note that you should being using POST requests, not GET requests. See: JSON Hijacking and How ASP.NET AJAX 1.0 Avoids these Attacks

---

EDIT

Based on the jQuery that you posted, you're not calling the correct method. You C# defines a method called GetMovies, yet your jQuery is attempting to call a method called `Movies'.

This:

url: "/MovieService.asmx/Movies"

Should change to this:

url: "/MovieService.asmx/GetMovies"