Mono.Xml.XmlTextWriter.DetermineAttributePrefix C# (CSharp) Method

		string DetermineAttributePrefix (
			string prefix, string local, string ns)
		{
			bool mockup = false;
			if (prefix.Length == 0) {
				prefix = LookupPrefix (ns);
				if (prefix != null && prefix.Length > 0)
					return prefix;
				mockup = true;
			} else {
				prefix = nsmanager.NameTable.Add (prefix);
				string existing = nsmanager.LookupNamespace (prefix, true);
				if (existing == ns)
					return prefix;
				if (existing != null) {
					// See code comment on the head of
					// this source file.
					nsmanager.RemoveNamespace (prefix, existing);
					if (nsmanager.LookupNamespace (prefix, true) != existing) {
						mockup = true;
						nsmanager.AddNamespace (prefix, existing);
					}
				}
			}

			if (mockup)
				prefix = MockupPrefix (ns, true);
			new_local_namespaces.Push (prefix);
			nsmanager.AddNamespace (prefix, ns);

			return prefix;
		}