Question

I have a class like this,

public class person
{
 name Name {set; get;}
 string Address {set; get;}
}

public class name
{
  string First {set; get;}
  string Last {set; get;}
}

Now when I create the object an try to set the first or last name I get an error. “Object reference not set to an instance of an object.”

person Person = new person();
Person.Name.First = "John";
Person.Name.Last ="Smith";

What am I doing wrong?

Answer 1

You need to initialise the name class instance too

person Person = new person();
Person.Name = new name();
Person.Name.First = "A";

You could also do this in the constructor of person if you wish

public class person
    {
        public name Name { set; get; }
        string Address { set; get; }

        public person()
        {
            Name = new name();
        }
    }

Or even try

person Person = new person { Name = new name { First = "A", Last = "B" } };