Check whether an array is a subset of another

Question

Any idea on how to check whether that list is a subset of another?

Specifically, I have

List t1 = new List { 1, 3, 5 };
L         


        

Answer 1

@Cameron's solution as an extension method:

public static bool IsSubsetOf(this IEnumerable a, IEnumerable b)
{
    return !a.Except(b).Any();
}

Usage:

bool isSubset = t2.IsSubsetOf(t1);

(This is similar, but not quite the same as the one posted on @Michael's blog)