XML DOM and QTP - Using VBScript

The XML DOM (XML Document Object Model) defines methods for accessing and manipulating XML documents.This topic will discuss how to manipulate  XML  using  vbscript and accessing information from XML.

Methods to Access XML DOM:

1. Creating an object for xmlDOM

set  xmldom = Createobject("MSXML.DOMDocument")

xmldom.async = “False”

2. Loading a file using xml DOM

Xmldom.Load(FileName)

3. To Find number of parent nodes in a xml

Intlen = Xmldom.childnodes.length

4. To find names of parent nodes

For i=0 to intlen-1

      strParNodeName = xmldom.childnodes(i).Name

Next

5. How to search a node with tagName

Set nodelist = xmldom.getElementsByTagName(strTagName)

This gives a collection of nodes with tag name as strTagName.

The tagName value "*" will returns all elements in the document.

6. How to extract information from nodelist using GetElementbyTagName

Set nodelist = xmldom.getElementsByTagName(strTagName)

For i= 0 to nodelist.length – 1

       strText = nodelist.item(i).xml;

       msgbox strText

Next

So points to remember in this are as follows:

• We can get all elements with the tagname using xmldom.getElementsByTagName

• Once we have the list, we can access each of the nodes in the list using item(index).property

• To access attribute property value for a node , use strText = nodelist.item(i).getattribute("category")

• To get xml content of a node, use strText = nodelist.item(i).xml

• Use strText = nodelist.item(i).nodeName to get the name of required node.

• Use strText = nodelist.item(i).text to get value in a particular node

Sample Code explaining the concept

FileName = "d:\xmldom.xml"

''Create an instance of xml dom

set  xmldom = Createobject("MSXML.DOMDocument")

''set async = "False"

xmldom.async = "False"

xmldom.Load(FileName)

intlen = xmldom.childnodes.length

msgbox intlen

Set nodelist = xmldom.getElementsByTagName("title")

msgbox nodelist.length

If nodelist.length > 0 then

    For each x in nodelist

        AttName=x.getattribute("lang")

        myname = x.Text

        msgbox AttName +" "+ myname

    Next

Else

    msgbox " field not found."

End If

7. Using Selectnodes method to extract information

FileName = "d:\xmldom.xml"

''Create an instance of xml dom

set  xmldom = Createobject("MSXML.DOMDocument")

''set async = "False"

xmldom.async = "False"

xmldom.Load(FileName)

intlen = xmldom.childnodes.length

msgbox intlen

Set nodelist = xmldom.selectNodes("/bookstore/book/title")

msgbox nodelist.length

If nodelist.length > 0 then

    For each x in nodelist

        AttName=x.getattribute("lang")

        myname = x.Text

        msgbox AttName +" "+ myname

    Next

Else

    msgbox " field not found."

End If

8. Using SelectSingleNode to extract information

FileName = "d:\xmldom.xml"

''Create an instance of xml dom

set  xmldom = Createobject("MSXML.DOMDocument")

''set async = "False"

xmldom.async = "False"

xmldom.Load(FileName)

''This will give 1^st item property matching the node structure

Msgbox xmldom.selectSingleNode("/bookstore/book/title").Text

''This will give 1^st item property matching the node structure with filter as attribute value

Msgbox xmldom.selectSingleNode("/bookstore/book/title[@lang = 'ke']").Text

''This will give 1^st item property matching the node structure with filter as text  value

Msgbox xmldom.selectSingleNode("/bookstore/book/title[.= 'Learning XML']").Text