Do I need two new List() constructors?

Question

I have the following class called Parent. It contains a list of ParentDetail classes:

public class Parent
{

    public Parent()
    {
       this._parentDetails = new List<ParentDetail>();
    }

    public IList<ParentDetail> ParentDetails
    {
        get { return _parentDetails; }
    }

    private List<ParentDetail> _parentDetails = new List<ParentDetail>();

}

public class ParentDetail
{
    public string FileName { get; set; }
}

The class seems to work but I don't understand why "= new List();" appears twice. Can someone explain in a couple of lines what is happening?

who says you need to initialize _parentDetails twice ? You do not. — Frederik Gheysels, Jun 22 '11 at 07:48
That seems to be redundant, either in constructor or inline but both is needless. — Tim Schmelter, Jun 22 '11 at 07:50

score 1 · Answer 1 · answered Jun 22 '11 at 07:48

1

Do I need two new List() constructors?

No, one of them would be enough - creating two instaces of which one will never be used is superfluous.

answered Jun 22 '11 at 07:48

Matthias

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score 1 · Answer 2 · answered Jun 22 '11 at 07:48

1

This is redundancy, which is not needed. Either one of them can be removed.

answered Jun 22 '11 at 07:48

Petar Ivanov

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score 0 · Answer 3 · answered Jun 22 '11 at 07:48

0

It doesn't have to, and shouldn't. In this case _parentDetails is initialised twice.

Both the assignments are equivalent in this case. For what it's worth I prefer initiailising in the default constructor, not the field/member declaration.

answered Jun 22 '11 at 07:48

Kieren Johnstone

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score 0 · Accepted Answer · edited May 23 '17 at 11:48

0

How about this

private List<ParentDetail> _parentDetails;
public Parent()
{
   this._parentDetails = new List<ParentDetail>();
}

Excellent explanation Here

edited May 23 '17 at 11:48

Community

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answered Jun 22 '11 at 07:49

V4Vendetta

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score 0 · Answer 5 · answered Jun 22 '11 at 07:53

I dont think the inline creation of new List<ParentDetail>(); is needed as it is already done inside your constructor..Or else you can remove the constructor as a whole...

The inline code when compiled creates a default constructor and moves that piece of code inside the constructor.

Do I need two new List() constructors?

5 Answers5