IXmlNamespaceResolver.LookupPrefix(String) Method


Gets the prefix that is mapped to the specified namespace URI.

 System::String ^ LookupPrefix(System::String ^ namespaceName);
public string LookupPrefix (string namespaceName);
public string? LookupPrefix (string namespaceName);
abstract member LookupPrefix : string -> string
Public Function LookupPrefix (namespaceName As String) As String



The namespace URI whose prefix you wish to find.



The prefix that is mapped to the namespace URI; null if the namespace URI is not mapped to a prefix.


It is possible for a namespace URI to be mapped to multiple prefixes. Because the prefixes are not mapped in a predictable manner, you should not depend on getting back a particular prefix when a namespace URI is mapped to more than one prefix.


Namespace URI to prefix mappings can change from node to node in an XML document. You cannot depend on the result of a lookup being consistent from one node to the next.

The following table describes how the default and built-in namespaces are handled by the LookupPrefix method.

Namespace Return value
http://www.w3.org/XML/1998/namespace xml
http://www.w3.org/2000/xmlns/ xmlns
An empty namespace. A default namespace that has not been defined.

Applies to