What ways are there for the controller to return json with empty property model or list, but not null

Example model:

 public class Model
        {
            public string name;
            public string comment;
            public List<Contact> Contacts;
        }
        public  class Contact
        {
            public int id;
            public string title;
        }
        static void Main(string[] args)
        {
            Model model1 = new Model() 
            { 
                name = "Max"
            };
        }

and if we have an empty list, then I want to get such a json:

{
   "name": "Max",
   "comment": "",
   "contacts": []
}

CodePudding user response：

You can use private fields

public class Model
{
    private string _name = "";
    private string _comment = "";
    private List<Contact> _contacts = new List<Contact>();

    public string Name
    {
        get
        {
            return _name;
        }
        set
        {
            if (_name != value) _name = value;
        }
    }

    public string Comment
    {
        get
        {
            return _comment;
        }
        set
        {
            if (_comment != value) _comment = value;
        }
    }

    public List<Contact> Contacts
    {
        get
        {
            return _contacts;
        }
        set
        {
            if (value != null && value.Length > 0) _contacts = value;
        }
    }
}

CodePudding user response：

Initializing Contacts will send empty set when your Serialize

public class Model
{
    public string name;
    public string comment;
    public List<Contact> Contacts = new List<Contact>();
}