c#的webapi且net451 两层实体类转json

假设有以下两层实体类：

public class User
{
    public int Id { get; set; }
    public string Name { get; set; }
    public DateTime Birthday { get; set; }

    public List<Address> Addresses { get; set; }
}

public class Address
{
    public string City { get; set; }
    public string Street { get; set; }
}

使用Newtonsoft.Json库可以将实体类转换为JSON格式的字符串。

using Newtonsoft.Json;

// ...

User user = new User
{
    Id = 1,
    Name = "John",
    Birthday = new DateTime(1990, 1, 1),
    Addresses = new List<Address>
    {
        new Address { City = "New York", Street = "Broadway" },
        new Address { City = "Los Angeles", Street = "Hollywood Blvd" }
    }
};

string json = JsonConvert.SerializeObject(user);
Console.WriteLine(json);

输出结果：

{
  "Id": 1,
  "Name": "John",
  "Birthday": "1990-01-01T00:00:00",
  "Addresses": [
    {
      "City": "New York",
      "Street": "Broadway"
    },
    {
      "City": "Los Angeles",
      "Street": "Hollywood Blvd"
    }
  ]
}