How to convert List> to an array of arrays

Question

What is the best way to convert a list into an array of type int[][]?

List> lst = new List>();


        

Answer 1

you can easily do it using linq.

int[][] arrays = lst.Select(a => a.ToArray()).ToArray();

but if you want another way you can loop through the list and manually generate the 2d array.

how to loop through nested list

Answer 2

There's no library function to do this.

You'll need to do this with loops.

int[][] newlist = new int[lst.Size][];
for (int i = 0; i < lst.Size; i++)
{
    List<int> sublist = lst.ElementAt(i);
    newlist[i] = new int[sublis.Size];
    for (int j = 0; j < sublist.Size; j++)
    {
        newlist[i][j] = sublist.ElementAt(j);
    }
}

There you go!

Answer 3

int[][] arrays = lst.Select(a => a.ToArray()).ToArray();

Answer 4

It's easy with LINQ:

lst.Select(l => l.ToArray()).ToArray()

If you really wanted two-dimentional array (int[,], not int[][]), that would be more difficult and the best solution would probably be using nested fors.