System.Xml.XmlWellFormedWriter.LookupNamespaceIndex C# (CSharp) Method

        private int LookupNamespaceIndex(string prefix)
        {
            int index;
            if (_useNsHashtable)
            {
                if (_nsHashtable.TryGetValue(prefix, out index))
                {
                    return index;
                }
            }
            else
            {
                for (int i = _nsTop; i >= 0; i--)
                {
                    if (_nsStack[i].prefix == prefix)
                    {
                        return i;
                    }
                }
            }
            return -1;
        }