JavaScript-从使用Json.Net创建的JSON对象提取数据

Question

I have a server-side method used to return the data to the user. The data is stored in a SQL Server database and is mapped using EF 6. Once extracted from the database using an id value, the object is subsequently serialized using the Json.NET framework. The object is used "as is", without filtering out the references to other tables. Because of that, I've had to use the "PreserveReferencesHandling" option. On the client-side, AJAX is used to call the method. I'm having trouble extracting the data from the object (client-side) which does get serialized and is delivered to the browser as expected.

Server-side method:

[WebMethod]
public static string ContactData(long id)
{
    IService<Contact> contactService = new ContactService();
    Contact contactEdit = contactService.GetById(id);

    string str = JsonConvert.SerializeObject(contactEdit, new JsonSerializerSettings
    {
        PreserveReferencesHandling = PreserveReferencesHandling.Objects
    });

    return str;
}

Client-side function (the important part):

$.ajax({
    type: "POST",
    url: "Contacts.aspx/ContactData",
    data: JSON.stringify({ id: contactId }), // id by which I am receiving the object
    contentType: "application/json; charset=utf-8",
    dataType: "json",
    success: function (contact) {
        $("#tbFirstName").val(contact.d[0].Contact.first_name); // I've tried various combinations to no avail
                },
});

This is how the JSON object (testing purposes data) looks like in Visual Studio's JSON Visualizer:

And this is what the browser (FF 32, it that matters) receives:

Firebug

I will post more info if needed.

Answer 1

First parse the json before you process it. and loop through it using jquery each function.

    $.ajax({
        type: "POST",
        url: "Contacts.aspx/ContactData",
        data: JSON.stringify({ id: contactId }), // id by which I am receiving the object
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function (contact)
                {
                    var contact=jQuery.parseJSON(contact);
                    $.each(contact, function(i, item) {
                        alert(i + " ==> "+  item.first_name);
                    });

                 }

    });