Represents a Processing Instruction.

If enabled, #PI pseudo-elements may appear as children of any normal XML elements as well as within the pseudo-element #DOCUMENT.

Value:

The content of this Processing Instruction.

Example:

The following Processing Instruction in an XML file:

<?php include("header.php");?>
will produce a #PI pseudo-element which, if it was a normal XML element, would look as the following:
<#PI target="php">include("header.php");</#PI>