Rip a Document to Pieces

More often than not, you do not program in a vacuum. That is true not only of the process and a team of people but with code itself. What I mean is that you typically do not simply build JavaScript (or some other code language) applications by themselves, but, rather, JavaScript interacts with HTML and CSS. HTML pages (or our content) are documents of text that are structured into pieces. When someone creates an HTML page, they create a hierarchical structure…head, body, header, section, nav, footer and more. The functionality of a web app is provided by JavaScript (typically). So, in order to have high quality, interactive, robust applications, JavaScript has to be able to work within and manipulate the HTML document. This is done utilizing what is known as the Document Object Model (DOM). JavaScript has built in functions/methods that allow a developer to pretty much do whatever they would like with an HTML document. Today I want to show one example…grabbing an element or tag by their ID.

Whenever I create an HTML document, I utilize the ID and class elements extensively. This is key for styling a page and for the interactivity. Let me show you how you can use the ID of an element to manipulate the DOM. First, let’s talk about IDs. The syntax for an ID is as follows…

[code lang=”js”]
<!– A typical HTML this case a form input tag. –>
<input type = "text" id = "someID" name = "someName">
<!– This code would result in a form text box being output to the HTML document. –>

Notice that I have the ID attribute with the value of “someID”. One thing to note about IDs is that they can only exist one time within any HTML document. What that means is that there can only be one element with the ID of “someID”. I cannot create another element and re-use that same ID. This is to our advantage, because we can use JavaScript to grab that element, in this case, the input tag.

So how do we do that? We use a function/method entitled, “getElementById()”. Here is an example…

[code lang=”js”]
// Create a variable to hold the information from our input tag element
var myVar;
// Grab the value of the input tag field and store it in myVar
myVar = document.getElementById("someID").value;

So the way this works is we tell the JavaScript interpreter to go into the document, get an element by the ID of someID and then grab the value of that element. Since this is a form field, what that means is we can grab whatever information the end user typed into the form text field. We can take that information and store it in a variable like I have done here and then do with it what we would like. FYI, in this case I am grabbing the element’s value, but you do not have to do that. You can simply grab the entire element without the “.value” on the end.

Happy Coding!

Clay Hess

More To Explore


Exploring the Broadcast Channel API: Inter-Tab Communication

Intercommunication between different contexts (like tabs, iframes or workers) of the same origin has often been a challenge. With the Broadcast Channel API, developers now have a powerful tool to easily communicate between browsing contexts. In this blog post, we’ll dive deep into the capabilities of the Broadcast Channel API, exploring its features, use cases, and how it can be effectively implemented in your projects.

computer, laptop, work place-2982270.jpg

Unlocking Wireless Communication: A Dive into the Bluetooth API

Wireless communication has become an integral part of our daily lives, and Bluetooth technology is at the forefront of this revolution, enabling devices to exchange data over short distances and creating a world more interconnected than ever before. At the heart of this technology lies the Bluetooth Application Programming Interface (API), a powerful tool for developers looking to harness the capabilities of Bluetooth in their applications. In this blog post, we’ll explore what the Bluetooth API is, how it works, and the possibilities it opens up for innovation in wireless communication.

Share This Post


Need help?

Let's have a chat...


Jump Back In!

Here at Webolution Designs, we love to learn. This includes sharing things we have learned with you. 


Begin Your Learning Journey Today!

Come back inside to continue your learning journey.