PrefixURI (XmlDoc/XmlNode function)

URI of specified prefix in context of selected node

PrefixURI is a member of the XmlDoc and XmlNode classes.

This function can get the Uniform Resource Identifier (URI) associated with a prefix, or it can get the default URI (if a node has a default namespace declaration), in the context of a node that is the head of an XPath result.

The PrefixURI function is new as of version 6.9 of the Sirius Mods.

Syntax

  %uri = nr:PrefixURI(prefix, [XPath])

Syntax Terms

%uri

A Unicode string variable for the returned URI.

nr

An XmlDoc or XmlNode, used as the context node for the XPath expression. If an XmlDoc, the Root node is the context node.

prefix

A Unicode string that is the prefix to “lookup” in the XmlDoc. If this is the null string, the %uri result is the default namespace at the node to process. Otherwise, the %uri result is the URI bound to prefix by a namespace declaration in scope at the node to process. In either case, the %uri result is null if there is no namespace associated with prefix. The prefix length must be at most 255 characters.

XPath

A Unicode string that is an XPath expression that results in a nodelist. The head of the nodelist is the node to process. An optional argument, its default is a period (.), that is, the node referenced by the method object (nr).

Usage Notes

• As of Sirius Mods version 7.3, the method's arguments and result may include only non-null EBCDIC characters that translate to Unicode. As of Sirius Mods version 7.6, these strings are Unicode or are converted to Unicode. For more information about the effects of this version 7.6 change, see Strings and Unicode. For an example of a specific effect that involves the Value method, see item ?? refid=univalx..

Example

In the following example, a node has a default URI defined as well as URIs for two prefixes. PrefixURI calls return the three URIs:

    Begin
    %d Object XmlDoc Auto New
    %n Object XmlNode
    %n = %d:AddElement('x', , 'urn:default')
    %n:AddNamespace('foo', 'urn:foo')
    %n:AddNamespace('bar', 'urn:bar')
    %n:Print
    Print 'Default namespace URI =' And %n:PrefixURI('')
    Print 'URI bound to prefix "foo" =' And %n:PrefixURI('foo')
    Print 'URI bound to prefix "bar" =' And %n:PrefixURI('bar')
    End

The following lines are printed:

    <x xmlns="urn:default" xmlns:foo="urn:foo" xmlns:bar="urn:bar"/>
    Default namespace URI = urn:default
    URI bound to prefix "foo" = urn:foo
    URI bound to prefix "bar" = urn:bar

Request-Cancellation Errors

• XmlDoc Namespace property not On.
• XPath is invalid.
• Result of (XPath) is empty.
• Insufficient free space exists in CCATEMP.

See Also

• For more information about using XPath expressions, see XPath.
• For more information about namespace declarations, see ?? refid=namsp..
• For more information about URIs, see ?? refid=nsuri..
• The DefaultURI method (??DefaultURI) returns the default URI, if a node has a default namespace declaration; otherwise it returns a null string. The URI method (?? refid=uri.) returns the URI bound to a node's name, if any.
• These methods add namespace URIs to XmlDoc nodes:
  • AddElement
  • AddAttribute
  • AddNamespace