How to initialize a list with constructor?

Question

I have a type:

public  class Human
{
    public int Id { get; set; }
    public string Address { get; set; }
    public string Name { get; set; }
    public List         


        

Answer 1

In general don't expose List publicly, and don't provide setters for collection properties. Also, you may want to copy the elements of the passed list (as shown below). Otherwise changes to the original list will affect the Human instance.

public class Human
{
    public Human()
    {
    }

    public Human(IEnumerable contactNumbers)
    {
        if (contactNumbers == null)
        {
            throw new ArgumentNullException("contactNumbers");
        }

        _contactNumbers.AddRange(contactNumbers);
    }

    public IEnumerable ContactNumbers
    {
        get { return _contactNumbers; }
    }

    private readonly List _contactNumbers = new List();
}

Another option is to use the list constructor that takes a collection and remove the field initializer.