Testing sets for equality (IEnumerable and IDictionary)

CollectionHelper.cs

using System;
using System.Collections;

public static class CollectionHelper {
    
    public static bool SetsEqual(IEnumerable set1, IEnumerable set2) {

        var h1 = new Hashtable();
        foreach ( var item in set1 ) {
            h1[item] = true;
        }

        foreach ( var item in set2 ) {
            if ( !h1.Contains(item)) {
                return false;
            }
        }

        return true;

    }

    public static bool SetsEqual(IDictionary h1, IDictionary h2) {

        if (h1.Count != h2.Count) {
            return false;
        }

        foreach ( object key in h1.Keys ) {

            if (!Object.Equals(h1[key], h2[key])) {
                return false;
            }

        }

        return true;

    }

}