System.Xml.XmlTextReaderImpl.SetupFromParserContext C# (CSharp) Method

        private void SetupFromParserContext(XmlParserContext context, XmlReaderSettings settings)
        {
            Debug.Assert(context != null);

            // setup nameTable
            XmlNameTable nt = settings.NameTable;
            _nameTableFromSettings = (nt != null);

            // get name table from namespace manager in XmlParserContext, if available; 
            if (context.NamespaceManager != null)
            {
                // must be the same as XmlReaderSettings.NameTable, or null
                if (nt != null && nt != context.NamespaceManager.NameTable)
                {
                    throw new XmlException(SR.Xml_NametableMismatch);
                }
                // get the namespace manager from context
                _namespaceManager = context.NamespaceManager;
                _xmlContext.defaultNamespace = _namespaceManager.LookupNamespace(string.Empty);

                // get the nametable from ns manager
                nt = _namespaceManager.NameTable;

                Debug.Assert(nt != null);
                Debug.Assert(context.NameTable == null || context.NameTable == nt, "This check should have been done in XmlParserContext constructor.");
            }
            // get name table directly from XmlParserContext
            else if (context.NameTable != null)
            {
                // must be the same as XmlReaderSettings.NameTable, or null
                if (nt != null && nt != context.NameTable)
                {
                    throw new XmlException(SR.Xml_NametableMismatch, string.Empty);
                }
                nt = context.NameTable;
            }
            // no nametable provided -> create a new one
            else if (nt == null)
            {
                nt = new NameTable();
                Debug.Assert(_nameTableFromSettings == false);
            }
            _nameTable = nt;

            // make sure we have namespace manager
            if (_namespaceManager == null)
            {
                _namespaceManager = new XmlNamespaceManager(nt);
            }

            // copy xml:space and xml:lang
            _xmlContext.xmlSpace = context.XmlSpace;
            _xmlContext.xmlLang = context.XmlLang;
        }