What is the best way to retrieve the true CSS property value of an HTML element node?

My understanding of the getComputedStyles() method is that it returns an object enabling access to the actual CSS property values of an HTML element node.

I decided to test this concept by creating a simple example with a paragraph that contains a span:

let span = document.getElementsByTagName("span")[0];
let style = window.getComputedStyle(span);
span.innerText = "span background-color is " + style.getPropertyValue("background-color");
<p style="background-color: orange">
  <span style="color: green">Empty</span>
</p>

The paragraph's background color is orange, so should the span inherit that property value, or am I mistaken? Could it be possible that inherited colors are not considered in getComputedStyles? If so, how can I retrieve the true visible background color for the span? Thank you.

javascripthtmlcssgetcomputedstyle

Answer №1

The result you are seeing is accurate.

The background-color of the span is rgba(0, 0, 0, 0)

Take note that the letter a in rgba is set to 0. This means there is no opacity present, rendering the element completely transparent.

Although it may appear orange, it is simply allowing visibility through to the orange element beneath it.

Answer №2

NOTE: Revised my response to utilize pure JavaScript for identifying the desired background color:

let span = document.getElementsByTagName("span")[0];
let parent = document.getElementsByTagName("span")[0].parentElement;
let style = window.getComputedStyle(parent);
span.innerText = "The background color of the span is " + style.getPropertyValue("background-color");
<p style="background-color: orange">
  <span style="color: green">Empty</span>
</p>

Another potential approach could involve adjusting the style of the span to inherit the parent's background color, making your initial attempt effective:

let span = document.getElementsByTagName("span")[0];
let style = window.getComputedStyle(span);
span.innerText = "The background color of the span is " + style.getPropertyValue("background-color");
<p style="background-color: orange">
  <span style="color: green; background-color: inherit">Empty</span>
</p>

Additionally, here is the previous version using JQuery:

var color = $('#getThis').closest("p").css("background-color");
$('#getThis').html('Background color is ' + color);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p style="background-color: orange">
  <span id="getThis" style="color: green">Empty</span>
</p>

Answer №3

I wanted to test the accuracy of getComputedStyle by creating a simple code snippet to see if it only returns the applied style for an element, rather than what is rendered.

let style1 = window.getComputedStyle(document.getElementById('s1'));
let style2 = window.getComputedStyle(document.getElementById('s2'));

document.getElementById('i1').value = style1.getPropertyValue("background-color");
document.getElementById('i2').value = style2.getPropertyValue("background-color");
<div style='background-color: cyan'>
  <span id='s1'>Span without backgound</span>
</div>

<div style='background-color: cyan'>
  <span id='s2' style='background-color: yellow'>Span with backgound</span>
</div>

<input id='i1' type='text' />
<input id='i2' type='text' />

However, I found the definition of getComputedStyle on W3Schools to be somewhat confusing:

The computed style is the style actually used in displaying the element, after "stylings" from multiple sources have been applied.

Upon reading this, it seems like all applied "stylings" should be returned, which doesn't align with my experience. This discrepancy has left me puzzled.

Answer №4

let span = document.getElementsByTagName("span")[0];
getBackgroundColor(span);


function getBackgroundColor(ele){
  let style = window.getComputedStyle(ele);
  if(ele){
    if(ele.style.backgroundColor)
      span.innerText = "span background-color is " + style.getPropertyValue("background-color");
    else
      getBackgroundColor(ele.parentNode);
  }else
    span.innerText = "span background is transparent";
  return;
}
<p style="background-color: orange">
  <span style="color: green">Empty</span>
</p>

This method utilizes recursion to continuously check the parent's background color until one is found, otherwise returning transparent.

Answer №5

By utilizing the following code snippet:

element.textContent = "The background color of element is " + style.getPropertyValue("color");

You will be able to obtain the text color rgb(0, 128, 0) just like when applied on element. Your code structure is providing an accurate result.

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Tips for integrating Tornado authentication with AngularJS

I have been experimenting with the authentication system outlined in the tornado documentation, and I am encountering a Cross-Origin Request issue when trying to integrate it with AngularJS. Is there a way to successfully combine Tornado's authentica ...

javascriptpythonangularjstornado

Having trouble getting Jquery Ajax Post to work properly when using JinJa Templating?

Objective: My goal is simple - to click a button and post information to a database. Problem: Unfortunately, clicking the button doesn't seem to be posting to the database as expected. Setup: I am working with Flask Framework, Jquery, and Jinja Temp ...

javascriptjqueryajaxjinja2

Incorporating an external HTML page's <title> tag into a different HTML page using jQuery

I am faced with a challenge involving two files: index.html and index2.html. Both of these files reside in the same directory on a local machine, without access to PHP or other server-side languages. My goal is to extract the <title>Page Title</ ...

javascriptjqueryhtmlfrontend

Enable or disable options with the user's permission

Currently, I am developing a WordPress plugin that will display a simple div on all pages. The code is set up to create the div, turn it into a shortcode, and then show it on each page. I want to include a checkbox in the admin settings so that users can ...

javascriptjqueryhtmlwordpress

Is there a way to retrieve a button element from a pug template?

Why can't I use a button in index.js from a pug template? Here is the code in my pug template: doctype html html head meta(charset='UTF-8') meta(http-equiv='X-UA-Compatible' content='IE=edge') meta(name=& ...

javascriptnode.jspug

Error encountered: Exceeded maximum update depth in Material UI Data Grid

Encountering an error or warning when inputting rows in the table that is causing the screen to freeze. Warning: Maximum update depth exceeded. This issue can arise when a component triggers setState within useEffect, but useEffect doesn't have a de ...

javascriptmaterial-ui

Updating the value of a global variable through dependency injection in AngularJS

One thing I consistently do is inject app.constant('DOCUMENT_ID', window.documentId || 1); into services, controllers, and directives. I'm now looking to convert DOCUMENT_ID into a global variable. The goal is for any changes made to DOCUME ...

javascriptangularjs

req.body returns as an empty object

I'm currently utilizing body-parser, but it seems to be malfunctioning without any clear indication of what the issue might be. app.js var createError = require('http-errors'); var express = require('express'); var path = require ...

javascriptnode.jsexpressbody-parser

The styling for the mat datepicker is not appearing as expected

I am facing an issue with the mat datepicker as its style is not displaying correctly on the web page. I attempted to add the necessary styling to the styles.less file. @import "~@angular/material/prebuilt-themes/indigo-pink.css"; I also made s ...

htmlangularbootstrap-4angular-material

Tips for adjusting the font size on the Google Maps mapType controller

Is it possible to adjust the font size of a Google Maps mapType controller using HTML or CSS? I've managed to change the size of the controller, but struggling with the font size. https://i.sstatic.net/1n9oU.png HTML: <div #map id="map" style=" ...

htmlcssgoogle-maps

The max-height property is not applied to a border-box div with padding

One technique we use is the percentage trick on paddings to maintain aspect ratio in a div as the user scales their window. Here's an example: .div { background: red; width: 80%; margin: 0 auto 10px; -webkit-box-sizing: border-box; ...

css

Comparable to LINQ SingleOrDefault()

I frequently utilize this particular pattern in my Typescript coding: class Vegetable { constructor(public id: number, public name: string) { } } var vegetableArray = new Array<Vegetable>(); vegetableArray.push(new Vegetable(1, "Carrot")); ...

javascriptlinqtypescripttypescript1.5

The default margin of an HTML element is set to fill the width of its containing div and cannot be overridden

As a budding web developer, I'm encountering a basic issue that has me scratching my head. Any assistance would be highly appreciated: Regardless of the width I specify for elements within a particular div container, both Safari and Chrome seem to au ...

htmlcsspositionmarginmargins

Starting a Vue.js app with preloaded data

I have a single file component named Foo: <template> <div> This is the main app. X is {{ x }}, y is {{ y }} </div> </template> <script> export default { data() { return { x: 'hello x' }; }, } </script> ...

javascriptvue.jsvuejs2

React search filter feature with dropdown selection

After successfully implementing a search filter in my React app, I encountered an issue when trying to incorporate a select tag to change the search filter criteria. class BookList extends Component { state = { search: '', selectedValue: ' ...

javascriptreactjs

Is the media-heading situated at the base of the picture?

Wondering if it's possible to create a horizontal list of images with the image-heading under each image using Bootstrap 3. I couldn't find any information on this in the documentation. <h5 class="media-heading pull-left">One</h5> &l ...

csstwitter-bootstraptwitter-bootstrap-3

Error in saving webpage as HTML

I have integrated FileSaver.js into my project to enable users to save web pages as HTML. The code below is triggered when a user clicks on the download button: var originalstr=$.ajax( { type: "GET", url:"url", async: false }).resp ...

javascriptjqueryhtmlajaxfilesaver.js

Transform an array of object's designated key values into a string that is separated by commas

Is there a way to convert specific key values of an object into a comma-separated string? I have been able to do this with arrays, but my current challenge is that my data is an array of objects. I want to convert each 'id' value into an array of ...

javascripttypescript

Retrieving FormData() parameters sent via Ajax with PHP

After successfully testing FormData() with jQuery.ajax, I encountered a roadblock when trying to implement a progress bar for file uploads using the same method. This led me to use AJAX directly and post form data, but unfortunately, retrieving the form da ...

phpjavascriptajax

The PHP implementation of Google reCAPTCHA is malfunctioning when combined with AJAX

I have a form on 100.php that makes an AJAX call to 200.php. <html> <head> <!-- Include the reCAPTCHA API JavaScript library provided by Google --> <script src='https://www.google.com/recaptcha/api.js'></script ...

javascriptphpjqueryhtmlajax