The createProcessingInstruction method creates a ProcessingInstruction object with the specified target name and data string. Creating an instance of this object does not automatically include it in the XML Document tree, and so its parentNode property is set to null.

The following example creates the ProcessingInstruction '<?xml version="1.0"?> and add it as the first child node of the document. To do this, the code uses the insertBefore method.

Code (VBScript):
Set objXMLDoc = CreateObject("Microsoft.XMLDOM")
objXMLDoc.async = False
objXMLDoc.load("quotations.xml")

Dim objNewPI, currNode
Set objNewPI = objXMLDoc.createProcessingInstruction("xml", " version = ""1.0""")
objXMLDoc.insertBefore objNewPI, objXMLDoc.firstChild

Set currNode = objXMLDoc.firstChild
document.write(currNode.nodeType)
document.write("<br>" & currNode.nodeName)
document.write("<br>" & currNode.nodeValue)

Output:
7
xml
version="1.0"

The value '7' returned for the node's type indicates that it is a ProcessingInstruction object (see the list of node types).