How to add custom properties to nodes and connectors?

var nodes = [];
var node = 
  {
   name: "node",
   //custom properties for node
   email:"gs@gmail.com",
   phone:"23456678",
  }
nodes.push(node);
var connectors=[];
var connector = 
   {
    name: "connector1",
    segments: [{ type:"straight" }], 
    //custom properties for connectors
    email:"gs@gmail.com",
    phone:"23456678",
   };
   connectors.push(connector);

public class CustomNode:Node
    {
        private string email;
        private string phone;
        [JsonProperty("email")]
        [DefaultValue("")]
        public string Email
        {
            get { return email; }
            set { email = value; }    
        }
        [JsonProperty("phone")]
        [DefaultValue("")]
        public string Phone
        {
            get { return phone; }
            set { phone = value; }
        }
}
CustomNode nodes = new CustomNode();
   nodes.Name = "Rectangle";
   //custom properties for node
   nodes.Email = "gs@gmail.com";
   nodes.Phone = "23456678";
model.Nodes.Add(nodes);
public class CustomConnector :Connector
    {
        private string email;
        private string phone;
        [JsonProperty("email")]
        [DefaultValue("")]
        public string Email
        {
            get { return email; }
            set { email = value; }    
        }
        [JsonProperty("phone")]
        [DefaultValue("")]
        public string Phone
        {
            get { return phone; }
            set { phone = value; }
        }
}
CustomConnector connectors = new CustomConnector();
    connectors.Name = "line";
    //custom properties for connectors
    connectors.Email = "gs@gmail.com";
    connectors.Phone = "23456678";
model.Connectors.Add(connectors);