Flatten jagged array in C# [duplicate]

Question

Is there an elegant way to flatten a 2D array in C# (using Linq or not)?

E.g. suppose

var my2dArray = new int[][] {
   new int[] {1,2,3},
   new int[] {4,5,6}
};

I want to call something like

my2dArray.flatten()

which would yield

{1,2,3,4,5,6}

Any ideas?

Answer 1

You can use SelectMany

var flat = my2dArray.SelectMany(a => a).ToArray();

This will work with a jagged array like in your example, but not with a 2D array like

var my2dArray = new [,] { { 1, 2, 3 }, { 1, 2, 3 } };

But in that case you can iterate the values like this

foreach(var item in my2dArray)
    Console.WriteLine(item);