Testing equality of arrays in C#

Question

I have two arrays. For example:

int[] Array1 = new[] {1, 2, 3, 4, 5, 6, 7, 8, 9}; int[] Array2 = new[] {9, 1, 4, 5, 2, 3, 6, 7, 8}; 

What is the best way to determine if they have the same elements?

Answer 1

You could also use SequenceEqual, provided the IEnumerable objects are sorted first.

int[] a1 = new[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };     int[] a2 = new[] { 9, 1, 4, 5, 2, 3, 6, 7, 8 };      bool equals = a1.OrderBy(a => a).SequenceEqual(a2.OrderBy(a => a)); 

Answer 2

By using LINQ you can implement it expressively and performant:

var q = from a in ar1         join b in ar2 on a equals b         select a;  bool equals = ar1.Length == ar2.Length && q.Count() == ar1.Length;