C# 3.0, object initializer and get property returning array, how to initialize?

Question

Having the following class:

public class SomeClass
{
    private readonly int[] _someThings;

    public SomeClass()
    {
        _someThings = new int[4];
    }

    public int[] SomeThings
    {
        get { return _someThings; }
    }
}

How would I use the object initializer syntax to initialize the SomeThings property like in the following (non-working) code extract?

var anObject = new SomeClass
    {
        SomeThings[0] = 4,
        SomeThings[3] = 8
    }

---

Update

One could do (even without a set property):

anObject.SomeThings[0] = 4;
anObject.SomeThings[3] = 8;

But I'm trying to use the object initializer syntax.

Answer 1

Object Initializer syntax is "syntatic sugar" for setting public properties.

There isn't a public setter for SomeThings, so you can't do it like this.

So, this...

Foo x = new Foo() { Bar = "cheese" };

... is the same as ...

Foo x = new Foo();
x.Bar = "cheese;

... and as such doesn't have any ability to reach into private members to set stuff.

Answer 2

AFAIK, You could only have a Add method like this:

public class SomeClass
{
  void Add(int index, int item) 
  { 
    // ...
  }
}

var anObject = new SomeClass()
    {
        {0, 4}, // Calls Add(0, 4)
        {4, 8}  // Calls Add(4, 8)
    }

Answer 3

Theoretically you could do it this way:

var anObject = new SomeClass {
    InitialSomeThings = new[] {
         1,
         2,
         3,
         4
    }
}

class SomeClass {
    private readonly int[] _somethings;
    public int[] 
       get { return _somethings; }
    }

    public int[] InitialSomeThings {
       set { 
           for(int i=0; i<value.Length; i++)
               _somethings[i] = value[i];
       }
   }
}

Answer 4

You could add an overloaded constructor:

public class SomeClass
{
    private readonly int[] _someThings;

    public SomeClass()
    {
        _someThings = new int[4];
    }

    public SomeClass(int[] someThings)
    {
        _someThings = someThings;
    }

    public int[] SomeThings
    {
        get { return _someThings; }
    }
}

...

        var anObject = new SomeClass(new [] {4, 8});