protected override object LookupNamedResource(DependencyObject dob, string name) { if (name == null) { throw new XamlParseException("you must specify a key in {StaticResource}"); } object o = parser.LookupNamedItem(target_element, name); if (o == null && !parsingBinding) { throw new XamlParseException(String.Format("Resource '{0}' must be available as a static resource", name)); } return(o); }