Slide 14.14: HTML DOM accessing nodes (cont.)

HTML DOM Accessing Nodes (Cont.)

DOM Node List
The getElementsByTagName method returns a node-list. A node-list is an array of nodes. The code on the right selects all <p> nodes in a node-list. The index starts at 0.

DOM Node List Length
The length property defines the number of nodes in a node-list. You can loop through a node-list by using the length property. The example performs the following two tasks:

Get all <p> element nodes.
For each <p> element, output the value of its text node.

Demonstration
The following demonstration shows how the script of HTML and JavaScript is displayed on the Web.


<html> <head> <script type="text/javascript"> function changeSize( ) { document.getElementById("mySelect").size=4; } </script> </head> <body> <form> <select id="mySelect"> <option>Apple</option> <option>Banana</option> <option>Orange</option> <option>Melon</option> </select> <input type="button" onclick="changeSize()" value="Change size"> </form> </body> </html>