XML DOM Add Nodes

Add a Node – appendChild()

The appendChild() method adds a child node to an existing node.

The new node is added (appended) after any existing child nodes.

Note: Use insertBefore() if the position of the node is important.

This code fragment creates an element (<edition>), and adds it after the last child of the first <book> element:

newEle = xmlDoc.createElement("edition");

xmlDoc.getElementsByTagName("book")[0].appendChild(newEle);

This code fragment does the same as above, but the new element is added with a value:

newEle = xmlDoc.createElement("edition");
newText=xmlDoc.createTextNode("first");
newEle.appendChild(newText);

xmlDoc.getElementsByTagName("book")[0].appendChild(newEle);

Insert a Node – insertBefore()

The insertBefore() method inserts a node before a specified child node.

This method is useful when the position of the added node is important:

newNode = xmlDoc.createElement("book");

x = xmlDoc.documentElement;
y = xmlDoc.getElementsByTagName("book")[3];

x.insertBefore(newNode,y);

If the second parameter of insertBefore() is null, the new node will be added after the last existing child node.

x.insertBefore(newNode,null) and x.appendChild(newNode) will both append a new child node to x.

Add a New Attribute

The setAttribute() method sets the value of an attribute.

xmlDoc.getElementsByTagName('book')[0].setAttribute("edition","first");

Note: If the attribute already exists, the setAttribute() method will overwrite the existing value.

Add Text to a Text Node – insertData()

The insertData() method inserts data into an existing text node.

The insertData() method has two parameters:

• offset – Where to begin inserting characters (starts at zero)
• string – The string to insert

The following code fragment will add “Easy” to the text node of the first <title> element of the loaded XML:

xmlDoc.getElementsByTagName("title")[0].childNodes[0].insertData(0,"Easy ");