Hiding C# properties when serialize with JSON.NET

Question

How can we hide the C# property where serializing with JSON.NET library. Suppose, we have class Customer

public class Customer
{
   public int CustId {get; set;}
   public string FirstName {get; set;}
   public string LastName {get; set;}
   public bool isLocked {get; set;}
   public Customer() {}

}

public class Test
{
  Customer cust = new Customer();
  cust.CustId = 101;
  cust.FirstName = "John"
  cust.LastName = "Murphy"

  string Json = JsonConvert.SerializeObject(cust); 
}

JSON

{   
    "CustId": 101,   
    "FirstName": "John",   
    "LastName": "Murphy",  
    "isLocked": false 
}

This object is converted to json, but i didn't specify the isLocked property. As library will serialize the entire class, is there any way to ignore a property during json serialization process or if we can add any attribute on the property.

EDIT: Also, If we create two instance of Customer class in an array. if we didn't specify is locked property on the second instance, can we can property hide for second object.

JSON

{
  "Customer": [
    {
      "CustId": 101,
      "FirstName": "John",
      "LastName": "Murphy",
      "isLocked": false
    },
    {
      "CustId": 102,
      "FirstName": "Sara",
      "LastName": "connie"
    }
  ]
}

Answer 1

Use the JSON.Net attributes:

public class Customer
{
   public int CustId {get; set;}
   public string FirstName {get; set;}
   public string LastName {get; set;}
   [JsonIgnore]
   public bool isLocked {get; set;}
   public Customer() {}

}

For more information: https://www.newtonsoft.com/json/help/html/SerializationAttributes.htm