HomeDHTML Page 5 - Rough Guide To The DOM (part 1)
Ducks In A Row - DHTML
It's the bane of Web developers everywhere - conflicting standards, browser incompatibilities, and code that changes every time a new browser version hits the Web. But fear not - charging in on a white steed comes a heroic knight, clad in the attire of the new W3C DOM and armed with the tools to make this nightmare end forever. Read on to find out how the new DOM finally brings some standards to the decidedly non-standard world of the Web.
In addition to the getElementById() method, which is typically used toobtain a reference to a specific element, the DOM also offers thegetElementsByTagName() method, used to return a collection of a specifictype of element. For example, the code
would return a collection, or array, containing references to all the<form> tags in the document. Each of these references is a node, and canthen be manipulated using the standard DOM methods and properties.
Consider the following document, which contains three <div>s, eachcontaining a line of text
Dewey in the house!
Yo dude! How's it hangin'?
and then study the code I'd use to manipulate the text within the second<div>
// get a list of all <div> tags
var divCollection = document.getElementsByTagName("div");
// get a reference to the second <div> in the collection
var deweyObj = divCollection;
// verify that we are where we think we are
// change the text string within the <div>
deweyObj.childNodes.data = "Dewey rocks!";
A collection of all the tags within a document (a lot like "document.all")can be obtained with