System.Security.Policy.ApplicationTrustCollection.GetEnumerator C# (CSharp) Method

    public System.Security.Policy.ApplicationTrustEnumerator GetEnumerator() { throw null; }
    public void Remove(System.Security.Policy.ApplicationTrust trust) { }

        public void AddRange(ApplicationTrustCollection trusts)
        {
            if (trusts == null)
            {
                throw new ArgumentNullException("trusts");
            }
            int num = 0;

            try
            {
                ApplicationTrustEnumerator enumerator = trusts.GetEnumerator();
                while (enumerator.MoveNext())
                {
                    ApplicationTrust current = enumerator.Current;
                    this.Add(current);
                    num++;
                }
            }
            catch
            {
                for (int i = 0; i < num; i++)
                {
                    this.Remove(trusts[i]);
                }
                throw;
            }
        }