February 5, 2002 - Adding An Attribute Node to An XML Tree | WebReference

February 5, 2002 - Adding An Attribute Node to An XML Tree

Yehuda Shiran February 5, 2002
Adding An Attribute Node to An XML Tree
Tips: February 2002

Yehuda Shiran, Ph.D.
Doc JavaScript

The addNode() function below creates a node of type "attribute":

function addNode() {
  var xmlDoc = new ActiveXObject("Msxml2.DOMDocument");
  var MyNode;
  var namedNodeMap;
  xmlDoc.async = false;
  xmlDoc.load("mydvd.xml");
  alert(xmlDoc.documentElement.xml);
  MyNode = xmlDoc.createNode("attribute", "Year", "");
  namedNodeMap = xmlDoc.documentElement.childNodes.item(0).attributes;
  namedNodeMap.setNamedItem(MyNode);
  alert(xmlDoc.documentElement.xml);
}
The node is an object. Let's add it to our mydvd tree, to the root's first child node. The root of the tree is <sales>. Its first child node, (see the tree representation in Column 101's Page 2), is <summary>. You usually start navigating the tree from the root. The root of the tree is:

  xmlDoc.documentElement;
The collection of the root's childNodes is:

  xmlDoc.documentElement.childNodes
The first item on this collection is the first child:

  xmlDoc.documentElement.childNodes.item(0)
The collection of attributes of this node (<summary>) is:


  xmlDoc.documentElement.childNodes.item(0).attributes
To insert the new node to this collection, you use the setNamedItem() method, with the new node object as a parameter: 

 
  xmlDoc.documentElement.childNodes.item(0).attributes.setNamedItem(MyNode)
Try it now. The first alert box echoes the XML file before adding the attribute node. The second alert box reflects the addition. Notice the Year attribute within the <summary> tag.