I have HahSet collection of int[9] arrays and want know if HashSe already contains that array. for example
HashSet<int[]> set = new HashSet<int[]>();
int[] a=new int[9]{1,2,3,4,5,6,7,8,9};
set.Add(a);
int[] a2=new int[9]{1,2,3,4,5,6,7,8,9};
if(!set.Contains(a2))
set.Add(a2);
How can I override or implement own Equals method so that HastSet.Contains would behave like Arrays.SequenceEquals?
You need to provide an implementation of IEqualityComparer<int[]>, and use the constructor that takes your custom comparer:
class MyEqCmpForInt : IEqualityComparer<int[]> {
public bool Equals(int[] a, int[] b) {
...
}
public int GetHashCode(int[] data) {
...
}
}
HashSet<int[]> set = new HashSet<int[]>(new MyEqCmpForInt());
The hash set class has a constructor that takes an equality comparer. Use it.
You'll have to implement your own array-equality comparer, such as the one listed here.
And then it's as simple as asking the hash-set to use your comparer:
var set = new HashSet<int[]>(new ArrayEqualityComparer<int>());
...
// You don't need to do a Contains check; it's implicit.
set.Add(someArray);
