Question

After reading this question here: Passing one Dimension of a Two Dimensional Array in C#, I wondered whether it’s possible to use some C# 4 trickery to bind one index of a multidimensional array. Hopefully something like this:

var matrix = new int[10, 20];
var row = <some dynamic magic with matrix, 7>;

And have row being semantically identical to matrix[7] – so that row[4] is exactly matrix[7, 4].

It’s quite easy to do with functions:

int some_func(int a, string b);
var some_func_5 = (b=>some_func(5, b));

Anyone has an idea?

Answer 1

I don’t think you can do anything particularly C#-4-specific here. I’d personally build a specific type for it:

public sealed class RectangularArrayView<T> : IList<T>
{
    private readonly int row;
    private readonly T[,] array;

    public RectangularArrayView(int row, T[,] array)
    {
        this.row = row;
        this.array = array;
    }

    public T this[int column]
    {
        get { return array[row, column]; }
        set { array[row, column] = value; }
    }

    // etc for other IList<T> methods; use explicit interface implementation
    // for things like Add which don't make sense on arrays
}