Fluent interfaces and inheritance in C#

Question

I\'ll show a problem by example. There is a base class with fluent interface:

class FluentPerson
{
    private string _FirstName = String.Empty;
    private          


        

Answer 1

You can use generics to achieve that.

public class FluentPerson
    where T : FluentPerson
{
    public T WithFirstName(string firstName)
    {
        // ...
        return (T)this;
    }

    public T WithLastName(string lastName)
    {
        // ...
        return (T)this;
    }
}

public class FluentCustomer : FluentPerson
{
    public FluentCustomer WithAccountNumber(string accountNumber)
    {
        // ...
        return this;
    }
}

And now:

var customer = new FluentCustomer()
  .WithAccountNumber("123")
  .WithFirstName("Abc")
  .WithLastName("Def")
  .ToString();