Easy-to-follow video tutorials help you learn software, creative, and business skills.Become a member

Working with restricted attributes

From: JavaScript: Enhancing the DOM

Video: Working with restricted attributes

The quickest way to work with element attributes is to use the dot notation. That's not always convenient because sometimes attribute names like class or for can be restricted in JavaScript. But there's another way of doing it. JavaScript provides a few functions for dealing with attributes. So, for example, you can use the getAttribute method to get the value of any attribute in an element. If you set attribute you can set the value of an existing attribute. You can check to see if an element has an attribute function. Finally, you can remove an attribute with the delete attribute function. So let's take a look at these in a document.

Working with restricted attributes

The quickest way to work with element attributes is to use the dot notation. That's not always convenient because sometimes attribute names like class or for can be restricted in JavaScript. But there's another way of doing it. JavaScript provides a few functions for dealing with attributes. So, for example, you can use the getAttribute method to get the value of any attribute in an element. If you set attribute you can set the value of an existing attribute. You can check to see if an element has an attribute function. Finally, you can remove an attribute with the delete attribute function. So let's take a look at these in a document.

Here's our web page. I'm going to go over to the registration page, and I'm going to pull up the console, Cmd+Option+I, Ctrl+Alt+I on a PC, and then hit escape. And then I'm going to create a variable called My Node, and pass it, and element in my DOM. (SOUND) So, I'm going to test that out. And you can see that I have the first label which has the word name in it. That has an attribute of 4 and we usually use that in JavaScript to create loops. So, we just can't use 4 in dot notation.

We would have to use htmlFor, and that would work. But for any of those attributes names that have funky names because they might be reserved words, it's easier to use some of these other functions. So, let's try getting the attribute for for, we'll use myNode and say getAttribute (SOUND) and type in for. That gives me the same thing, and I didn't have to remember the weird name, html4. To set an attribute, you can pass it to parameters. So let's go ahead and change this for attribute to something else.

We'll use set attribute, and we'll pass it the four value because we want to change the for attribute, and then we'll just set it to something else. Hit Return and pull out myNode again. And now you can see that it has the value somethingelse. In addition to that, you can find out if a node has an existing attribute with the hasAttribute function. So we use myNode and ask if it has an attribute of ID. And, of course, that returns false because it doesn't have an attribute of ID.

So if I ask if it has an attribute for, then it returns true. Finally, of course, it can remove an existing attribute. We can use my node and then remove attribute. And passed the attribute that we want to renew. For, and that get's rid of it. So let's check my node and return. And there it is. It now has no for attribute. So though these are a little bit harder to use than dot notation, they're more reliable and work with any attributes that might be restricted JavaScript names.

So, sometimes it's just easier to use these methods.

Show transcript

This video is part of

Image for JavaScript: Enhancing the DOM
JavaScript: Enhancing the DOM

36 video lessons · 7873 viewers

Ray Villalobos
Author

 
Expand all | Collapse all
  1. 2m 36s
    1. Welcome
      59s
    2. What you should know before watching this course
      50s
    3. Using the exercise files
      47s
  2. 24m 33s
    1. What is the Document Object Model (DOM)?
      3m 2s
    2. Navigating the DOM with developer tools
      8m 10s
    3. Testing JavaScript commands with the console
      5m 50s
    4. Communicating with the console through JavaScript
      7m 31s
  3. 31m 9s
    1. Selecting elements with getElementById
      4m 10s
    2. Choosing elements by HTML tag
      3m 20s
    3. Isolating elements by class name
      3m 12s
    4. Querying CSS to select elements
      4m 54s
    5. Working with named form elements
      3m 39s
    6. Understanding nodeType, nodeName, and nodeValue
      4m 30s
    7. Traversing up and down DOM nodes
      4m 40s
    8. Targeting node elements
      2m 44s
  4. 22m 25s
    1. Changing HTML attributes
      5m 25s
    2. Working with restricted attributes
      2m 49s
    3. Detecting data attributes
      3m 29s
    4. Controlling classes with the HTML5 classList
      3m 21s
    5. Targeting the attributes property
      1m 24s
    6. Using text content modifiers
      3m 42s
    7. Modifying elements as text
      2m 15s
  5. 14m 57s
    1. Creating and appending nodes
      4m 27s
    2. Controlling node insertions with insertBefore
      3m 17s
    3. Cloning and removing nodes
      4m 41s
    4. Replacing existing nodes
      2m 32s
  6. 26m 14s
    1. What we'll build
      2m 16s
    2. Adding a bubbling event listener
      4m 11s
    3. Creating and styling an overlay with JavaScript
      4m 39s
    4. Adding an image
      3m 48s
    5. Resizing images in the DOM
      2m 59s
    6. Centering an image
      2m 36s
    7. Handling clicks
      1m 29s
    8. Adjusting for scrolling
      1m 36s
    9. Detecting and adjusting for a window resize
      2m 40s
  7. 1m 49s
    1. Next steps
      1m 49s

Start learning today

Get unlimited access to all courses for just $25/month.

Become a member
Sometimes @lynda teaches me how to use a program and sometimes Lynda.com changes my life forever. @JosefShutter
@lynda lynda.com is an absolute life saver when it comes to learning todays software. Definitely recommend it! #higherlearning @Michael_Caraway
@lynda The best thing online! Your database of courses is great! To the mark and very helpful. Thanks! @ru22more
Got to create something yesterday I never thought I could do. #thanks @lynda @Ngventurella
I really do love @lynda as a learning platform. Never stop learning and developing, it’s probably our greatest gift as a species! @soundslikedavid
@lynda just subscribed to lynda.com all I can say its brilliant join now trust me @ButchSamurai
@lynda is an awesome resource. The membership is priceless if you take advantage of it. @diabetic_techie
One of the best decision I made this year. Buy a 1yr subscription to @lynda @cybercaptive
guys lynda.com (@lynda) is the best. So far I’ve learned Java, principles of OO programming, and now learning about MS project @lucasmitchell
Signed back up to @lynda dot com. I’ve missed it!! Proper geeking out right now! #timetolearn #geek @JayGodbold
Share a link to this course

What are exercise files?

Exercise files are the same files the author uses in the course. Save time by downloading the author's files instead of setting up your own files, and learn by following along with the instructor.

Can I take this course without the exercise files?

Yes! If you decide you would like the exercise files later, you can upgrade to a premium account any time.

Become a member Download sample files See plans and pricing

Please wait... please wait ...
Upgrade to get access to exercise files.

Exercise files video

How to use exercise files.

Learn by watching, listening, and doing, Exercise files are the same files the author uses in the course, so you can download them and follow along Premium memberships include access to all exercise files in the library.


Exercise files

Exercise files video

How to use exercise files.

For additional information on downloading and using exercise files, watch our instructional video or read the instructions in the FAQ.

This course includes free exercise files, so you can practice while you watch the course. To access all the exercise files in our library, become a Premium Member.

Join now "Already a member? Log in

Are you sure you want to mark all the videos in this course as unwatched?

This will not affect your course history, your reports, or your certificates of completion for this course.


Mark all as unwatched Cancel

Congratulations

You have completed JavaScript: Enhancing the DOM.

Return to your organization's learning portal to continue training, or close this page.


OK
Become a member to add this course to a playlist

Join today and get unlimited access to the entire library of video courses—and create as many playlists as you like.

Get started

Already a member?

Become a member to like this course.

Join today and get unlimited access to the entire library of video courses.

Get started

Already a member?

Exercise files

Learn by watching, listening, and doing! Exercise files are the same files the author uses in the course, so you can download them and follow along. Exercise files are available with all Premium memberships. Learn more

Get started

Already a Premium member?

Exercise files video

How to use exercise files.

Ask a question

Thanks for contacting us.
You’ll hear from our Customer Service team within 24 hours.

Please enter the text shown below:

The classic layout automatically defaults to the latest Flash Player.

To choose a different player, hold the cursor over your name at the top right of any lynda.com page and choose Site preferencesfrom the dropdown menu.

Continue to classic layout Stay on new layout
Exercise files

Access exercise files from a button right under the course name.

Mark videos as unwatched

Remove icons showing you already watched videos if you want to start over.

Control your viewing experience

Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.

Interactive transcripts

Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.

Are you sure you want to delete this note?

No

Your file was successfully uploaded.

Thanks for signing up.

We’ll send you a confirmation email shortly.


Sign up and receive emails about lynda.com and our online training library:

Here’s our privacy policy with more details about how we handle your information.

Keep up with news, tips, and latest courses with emails from lynda.com.

Sign up and receive emails about lynda.com and our online training library:

Here’s our privacy policy with more details about how we handle your information.

   
submit Lightbox submit clicked
Terms and conditions of use

We've updated our terms and conditions (now called terms of service).Go
Review and accept our updated terms of service.