BplusDotNet.xBplusTreeBytes.NextKey C# (CSharp) Method

        public string NextKey(string AfterThisKey)
        {
            xBucket bucket;
            string prefix;
            string result = null;
            bool found = FindBucketForPrefix(AfterThisKey, out bucket, out prefix, false);
            if (found)
            {
                result = bucket.NextKey(AfterThisKey);
                if (result!=null)
                {
                    return result;
                }
            }
            // otherwise look in the next bucket
            string nextprefix = this.tree.NextKey(prefix);
            if (nextprefix==null)
            {
                return null;
            }
            byte[] databytes = this.tree[nextprefix];
            bucket = new xBucket(this);
            bucket.Load(databytes);
            if (bucket.Count()<1)
            {
                throw new BplusTreeException("empty bucket loaded");
            }
            return bucket.FirstKey();
        }