namespace ConsoleApplication1
public static void Main()
var collection1 = new[] {1, 1, 3, 4, 5};
var collection2 = new[] {1, 3, 1, 4, 5};
var result = IsAllContains(collection1, collection2);
Console.WriteLine(result);
public static bool IsAllContains(int[] collection1, int[] collection2)
var buffer = collection2.ToList();
foreach (var item in collection1)
if (buffer.Contains(item))