The history of the Document Object Model is intertwined with the history of the " browser wars" of the late 1990s between Netscape Navigator and Microsoft Internet Explorer, as well as with that of JavaScript and JScript, the first scripting languages to be widely implemented in the JavaScript engines of web browsers. Text inserted into HTML elements are text nodes.All HTML attributes are attribute nodes.In HTML DOM (Document Object Model), every element is a node: The W3C now publishes stable snapshots of the WHATWG standard. WHATWG took over the development of the standard, publishing it as a living document. The principal standardization of the DOM was handled by the World Wide Web Consortium (W3C), which last developed a recommendation in 2004. Once an event is triggered, the event handlers get executed. Nodes can have event handlers attached to them. DOM methods allow programmatic access to the tree with them one can change the structure, style or content of a document. Each branch of the tree ends in a node, and each node contains objects. The DOM represents a document with a logical tree. It's true that every browser supports for (duh!), but experience proved that something that iterates over a collection for us is simpler as it doesn't force us to take care of a variable for counting, while the (relatively) complex - although well-known - syntax of for is prone to mistakes.The Document Object Model ( DOM) is a cross-platform and language-independent interface that treats an HTML or XML document as a tree structure wherein each node is an object representing a part of the document. a simple for statement would have worked. Quite heavy when it comes to memory consumption and CPU usage.Ĭonclusion: use document.querySelectorAll instead (which returns a NodeList). It's a live collection that gets updated when the DOM changes. and something that should be avoided in general. Now, the former does have forEach defined - but it's pretty much the only array method that has been added to its prototype so far.īut it's only a relatively recent addition, so older browsers don't support it - fortunately, the Array#forEach trick works pretty well, down to sufficiently old Internet Explorer versions (probably 6? 5.5? The heck am I saying, that could work for slice, but forEach was added only in IE9.).Ī HTMLCollection is a totally different beast. A small correction: you used document.getElementsB圜lassName which does not return a NodeList but a HTMLCollection.
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