JavaScript and HTML DOM

WORKING WITH THE DOM

In many cases, working with the DOM is fairly straightforward, making it easy to re-create with
JavaScript what normally would be created using HTML code.


 
Dynamic Scripts
The <script> element is used to insert JavaScript code into the page, either using by the src attribute
to include an external fi le or by including text inside the element itself. Dynamic scripts are those
that don’t exist when the page is loaded but are included later by using the DOM. As with the
HTML element, there are two ways to do this: pulling in an external fi le or inserting text directly.
Dynamically loading an external JavaScript fi le works as you would expect. Consider the following
<script> element:

<script type=”text/javascript” src=”client.js”></script>
This <script> element includes the text for the Chapter 9 client-detection script. The DOM code to
create this node is as follows:
var script = document.createElement(“script”);
script.type = “text/javascript”;
script.src = “client.js”;
document.body.appendChild(script);
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