XML DOM - Add Nodes

From http://www.w3schools.com (Copyright Refsnes Data)

# XML DOM Add Nodes

## Examples

The examples below use the XML file books.xml.
A function, loadXMLDoc(), in an external JavaScript is used to load the XML file.

Add a node after the last child node
This example uses appendChild() to add a child node to an existing node.

Add a node before a specified child node
This example uses insertBefore() to insert a node before a specified child node.

Add a new attribute
This example uses the setAttribute() method to add a new attribute.

Add data to a text node
This example uses insertData() to insert data into an existing text node.

## 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.

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

    xmlDoc=loadXMLDoc("books.xml");

    newel=xmlDoc.createElement("edition");

    x=xmlDoc.getElementsByTagName("book")[0];
    x.appendChild(newel);

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Create a new node <edition>
3. Append the node to the first <book> element

Try it yourself

Loop through and append an element to all <book> elements: Try it yourself

## Insert a Node - insertBefore()

The insertBefore() method is used to insert a node before a specified child node.

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

    xmlDoc=loadXMLDoc("books.xml");

    newNode=xmlDoc.createElement("book");

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

    x.insertBefore(newNode,y);

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Create a new element node <book>
3. Insert the new node in front of the last <book> element node

Try it yourself

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

There is no method called addAtribute().

The setAttribute() method creates a new attribute if the attribute does not exist:

    xmlDoc=loadXMLDoc("books.xml");

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

Example explained:

1. Load "books.xml" into xmlDoc using loadXMLDoc()
2. Set (create) the attribute "edition" with the value "first" for the first <book> element

Try it yourself

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=loadXMLDoc("books.xml");

    x=xmlDoc.getElementsByTagName("title")[0].childNodes[0];

    x.insertData(0,"Easy ");

Try it yourself

From http://www.w3schools.com (Copyright Refsnes Data)