IXmlNamespaceResolver.LookupPrefix(String) Method

Definition

Namespace:

System.Xml

Assembly:

System.Xml.ReaderWriter.dll

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

public:
 System::String ^ LookupPrefix(System::String ^ namespaceName);

public string? LookupPrefix (string namespaceName);

abstract member LookupPrefix : string -> string

Public Function LookupPrefix (namespaceName As String) As String

Parameters

namespaceName

String

The namespace URI whose prefix you wish to find.

Returns

String

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

Remarks

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.

Note

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.