c# Array.FindAllIndexOf which FindAll IndexOf

Question

I know c# has Array.FindAll and Array.IndexOf.

Is there a Array.FindAllIndexOf which returns int[]?

Answer 1

No, there is not. But you can write your own extension method.

public static int[] FindAllIndexOf(this T[] a, Predicate match)
{
   T[] subArray = Array.FindAll(a, match);
   return (from T item in subArray select Array.IndexOf(a, item)).ToArray();
}

and then, for your array, call it.