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:

Example

newEle = xmlDoc.createElement("edition");

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

Example explained:

1. Suppose "books.xml" is loaded into xmlDoc
2. Create a new node <edition>
3. Append the node to the first <book> element

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

Example

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

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

Example explained:

1. Suppose "books.xml" is loaded into xmlDoc
2. Create a new node <edition>
3. Create a new text node "first"
4. Append the text node to the <edition> node
5. Append the <addition> node to the <book> element

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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:

Example

newNode = xmlDoc.createElement("book");

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

x.insertBefore(newNode,y);

Example explained:

1. Suppose "books.xml" is loaded into xmlDoc
2. Create a new element node <book>
3. Insert the new node in front of the last <book> element node

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.

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Add a New Attribute

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

Example

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

Example explained:

1. Suppose "books.xml" has been loaded into xmlDoc
2. Set the value of the attribute "edition" to "first" for the first <book> element

There is no method called add Attribute()
The setAttribute() will create a new attribute if the attribute does not exist.

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

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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:

Example

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