在C＃中将json对象列表反序列化为POCO对象

Question

I am making a call to a servie that returns a list of jso serialized objects such as this:

{"employees":[{"employee":{"id":"1","date_created":"2011-06-16T15:03:27Z","extended":[{"address":{"street1":"12345 first st.","city":"Denver","state":"CO"}}]}},{"employee":{"id":"2"...

So, you can see I first-off have a list of employee objects called employees. On top of that, each employee object contains another object called extended for extended info (in this case address info). What I would like to acheive is passing in the entire list as a string to a deserializer and getting back a List with the Employee object looking like this:

[Serializable]
public class Employee    {
    public string Id { get; set; }
    public string DateCreated { get; set; }
    public ExtendedProperties Address { get; set; }
}

[Serializable]
public class ExtendedProperties
{
    public string Street1 { get; set; }
    public string City { get; set; }
    public string State { get; set; }
}

I have found similar examples using NEwtonSoft but they are not quite the same in terms of the composite object. If needed I can drop the extended properties. But that would be far from ideal.

Any help would be greatly appreciated.

TIA!

Answer 1

Well, there are a few things here:

• You've got an outer "wrapper" level or two, mapping the employees property to the actual collection of properties. You can either deal with that with a separate class, or read the whole thing using LINQ to JSON and then dig in one layer before deserializing the collection.
• It looks like you've actually got a collection of extended properties per employee, with one property of extended properties being the address.
• I'm not sure how to persuade the JSON library to convert date_created to DateCreated , although I dare say it could.

I've hacked up something to read this - but it's a bit ugly:

using System;
using System.Collections.Generic;
using System.IO;

using Newtonsoft.Json;

public class EmployeeCollection {
    public List<EmployeeWrapper> Employees { get; set; }
}

public class EmployeeWrapper {
    public Employee Employee { get; set; }
}

public class Employee    {
    public string Id { get; set; }
    public string Date_Created { get; set; }
    public List<ExtendedProperty> Extended  { get; set; }
}

public class ExtendedProperty {
    public Address Address { get; set; }
}

public class Address
{
    public string Street1 { get; set; }
    public string City { get; set; }
    public string State { get; set; }
}

class Test
{ 
    static void Main() 
    {
        string json = @"{""employees"":
            [{""employee"":
                {""id"":""1"",
                 ""date_created"":""2011-06-16T15:03:27Z"",
                 ""extended"":[
                    {""address"":
                    {""street1"":""12345 first st."",
                     ""city"":""Denver"",
                     ""state"":""CO""}}]
              }}]}";


        var employees =
             JsonConvert.DeserializeObject<EmployeeCollection>(json);
        foreach (var employeeWrapper in employees.Employees)
        {
            Employee employee = employeeWrapper.Employee;
            Console.WriteLine("ID: {0}", employee.Id);
            Console.WriteLine("Date created: {0}", employee.Date_Created);
            foreach (var prop in employee.Extended)
            {
                Console.WriteLine("Extended property:");
                Address addr = prop.Address;
                Console.WriteLine("{0} / {1} / {2}", addr.Street1,
                                  addr.City, addr.State);
            }
        }
    }     
}

If you want to keep your original class structure, I suggest you use LINQ to JSON to do a more manual conversion. It's not terribly hard, when you get used to the JSON library - particularly if you're happy with LINQ to Objects.