Only using a class within another class

Question

        public class ClientData : IEquatable<ClientData>
        {
            public String CustomerName { get; set; }
            public int CustomerId { get; set; }        

            public bool Equals(ClientData other)
            {
                if (other == null) return false;
                return (CustomerName == other.CustomerName && CustomerId == other.CustomerId);
            }

            public override int GetHashCode()
            {
                int hash = 23;
                hash = hash * 31 + CustomerName.GetHashCode();
                hash = hash * 31 + CustomerId.GetHashCode();
                return hash;
            }

        }

and

public class Service
{
    ....
}

I'm looking for a way to use my ClientData but only within my service class i.e only the service class knows that the clientdata class exists and can use its methods normally

Answer 1

You can make it a nested class e.g.:

public class Service
{
    private class ClientData : IEquatable<ClientData>
    {
       ...
    }
}

Answer 2

Make CientData a private nested class of Service:

public class Service
{
    private class ClientData
    {
        // ...
    }
}