Difference between Multidimensional Array notations (object[][] and object[,])

Question

I am wondering what is the difference between the two ways to define a Multidimensional Array in C#.

You can use object[][] and object[,] to work with multidimensional array.

Are there functional differences?

http://stackoverflow.com/questions/597720/what-is-differences-between-multidimensional-array-and-array-of-arrays-in-c — Jodrell, Jul 04 '12 at 14:29
Possible duplicate _exactly_: http://stackoverflow.com/q/597720 — mmdemirbas, Jul 04 '12 at 14:29

Matzi · Accepted Answer · 2012-07-04T14:38:34.320

8

The object[][] is a notation for array of arrays. The second one object[,] is a two dimensional array.

The main difference is while the first one can contain different length "inner" arrays, the second one must be rectangular (e.g. 4x7).

Example:

int[][] a = new int[] { new int[]{ 1, 2 }, new int[]{ 3, 4, 5, 6, 7 }};
int[,] b = new int[,] { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 } };

edited Jul 04 '12 at 14:38

answered Jul 04 '12 at 14:27

Matzi

1

@MAfifi No, rectangular. It's possible to have 16 x 9 for example using `object[,]` – Simon Forsberg Jul 04 '12 at 14:29

1 Answers1