How to read css

How to read CSS rule values with JavaScript?

Set the style of an outline Set the color of an outline Set the width of an outline Use the shorthand outline property Add space between an outline and the edge/border of an element CSS outline properties explained CSS Text Set the text color of different elements Align the text Remove the line under links Decorate the text Control the letters in a text Indent text Specify the space between characters Specify the space between lines Set the text direction of an element Increase the white space between words Specify a text shadow for an element Disable text wrapping inside an element Vertical alignment of an image inside text CSS text properties explained CSS Fonts Set the font of a text Set the size of the font Set the size of the font in px Set the size of the font in em Set the size of the font in percent and em Set the style of the font Set the variant of the font Set the boldness of the font All the font properties in one declaration Font properties explained CSS Icons Font Awesome icons Bootstrap icons Google icons CSS icons explained CSS Links Add different colors to visited/unvisited links Use of text-decoration on links Specify a background color for links Add other styles to hyperlinks Different types of cursors Advanced — Create link boxes Advanced — Create link boxes with borders CSS link properties explained CSS Lists All the different list item markers in lists Set an image as the list-item marker Position the list-item marker Remove default list settings All list properties in one declaration Style lists with colors Full-width bordered list CSS list properties explained CSS Tables Specify a black border for table, th, and td elements Use of border-collapse Single border around the table Specify the width and height of a table Set the horizontal alignment of content (text-align) Set the vertical alignment of content (vertical-align) All the background properties in one declaration Advanced background example CSS background properties explained CSS Borders Set the width of the four borders Set the width of the top border Set the width of the bottom border Set the width of the left border Set the width of the right border Set the style of the four borders Set the style of the top border Set the style of the bottom border Set the style of the left border Set the style of the right border Set the color of the four borders Set the color of the top border Set the color of the bottom border Set the color of the left border Set the color of the right border All the border properties in one declaration Add rounded borders to an element Set different borders on each side All the top border properties in one declaration All the bottom border properties in one declaration All the left border properties in one declaration All the right border properties in one declaration CSS border properties explained CSS Margins Specify different margins for each side of an element Use shorthand margin property with four values Use shorthand margin property with three values Use shorthand margin property with two values Use shorthand margin property with one value Set margin to auto to center the element within its container Let the left margin be inherited from the parent element Margin collapse Margin properties explained CSS Padding Specify different padding for each side of an element Use shorthand padding property with four values Use shorthand padding property with three values Use shorthand padding property with two values Use shorthand padding property with one value Padding and element width (without box-sizing) Padding and element width (with box-sizing)

Get a CSS value with JavaScript

I know I can set a CSS value through JavaScript such as:

document.getElementById('image_1').style.top = '100px'; 

But, can I get a current specific style value? I’ve read where I can get the entire style for the element, but I don’t want to have to parse the whole string if I don’t have to.

You can use getComputedStyle() .

 var element = document.getElementById('image_1'), style = window.getComputedStyle(element), top = style.getPropertyValue('top'); console.log(top);

The element.style property lets you know only the CSS properties that were defined as inline in that element (programmatically, or defined in the style attribute of the element), you should get the computed style.

Is not so easy to do it in a cross-browser way, IE has its own way, through the element.currentStyle property, and the DOM Level 2 standard way, implemented by other browsers is through the document.defaultView.getComputedStyle method.

The two ways have differences, for example, the IE element.currentStyle property expect that you access the CSS property names composed of two or more words in camelCase (e.g. maxHeight, fontSize, backgroundColor, etc), the standard way expects the properties with the words separated with dashes (e.g. max-height, font-size, background-color, etc). .

function getStyle(el, styleProp) < var value, defaultView = (el.ownerDocument || document).defaultView; // W3C standard way: if (defaultView && defaultView.getComputedStyle) < // sanitize property name to css notation // (hyphen separated words eg. font-Size) styleProp = styleProp.replace(/([A-Z])/g, "-$1").toLowerCase(); return defaultView.getComputedStyle(el, null).getPropertyValue(styleProp); >else if (el.currentStyle) < // IE // sanitize property name to camelCase styleProp = styleProp.replace(/\-(\w)/g, function(str, letter) < return letter.toUpperCase(); >); value = el.currentStyle[styleProp]; // convert other units to pixels on IE if (/^\d+(em|pt|%|ex)?$/i.test(value)) < return (function(value) < var oldLeft = el.style.left, oldRsLeft = el.runtimeStyle.left; el.runtimeStyle.left = el.currentStyle.left; el.style.left = value || 0; value = el.style.pixelLeft + "px"; el.style.left = oldLeft; el.runtimeStyle.left = oldRsLeft; return value; >)(value); > return value; > > 

Main reference stackoverflow

Use the following. It helped me.

document.getElementById('image_1').offsetTop 

Cross-browser solution to checking CSS values without DOM manipulation:

function get_style_rule_value(selector, style) < for (var i = 0; i < document.styleSheets.length; i++) < var mysheet = document.styleSheets[i]; var myrules = mysheet.cssRules ? mysheet.cssRules : mysheet.rules; for (var j = 0; j < myrules.length; j++) < if (myrules[j].selectorText && myrules[j].selectorText.toLowerCase() === selector) < return myrules[j].style[style]; >> > >; 

get_style_rule_value('.chart-color', 'backgroundColor') 

Sanitized version (forces selector input to lowercase, and allows for use case without leading «.»)

function get_style_rule_value(selector, style) < var selector_compare=selector.toLowerCase(); var selector_compare2= selector_compare.substr(0,1)==='.' ? selector_compare.substr(1) : '.'+selector_compare; for (var i = 0; i < document.styleSheets.length; i++) < var mysheet = document.styleSheets[i]; var myrules = mysheet.cssRules ? mysheet.cssRules : mysheet.rules; for (var j = 0; j < myrules.length; j++) < if (myrules[j].selectorText) < var check = myrules[j].selectorText.toLowerCase(); switch (check) < case selector_compare : case selector_compare2 : return myrules[j].style[style]; >> > > > 

Get a CSS value with JavaScript, check before use. You can use computedStyleMap () The answer is valid but sometimes you need to check what unit it returns, you can get that without any slice () or substring () string. var element = document.querySelector (‘.js-header-rep’); element.computedStyleMap ().get (‘padding-left’);

How to read CSS rule values with JavaScript?

CSS rules can be read and manipulated using DOM (Document Object Model). To read all the Embedded CSS rules using JavaScript we can use the following approaches.

• Use document.getElementsByTagName(“STYLE”); and get all the CSS tag.
• Check if the length is 0 then ‘no style tag used’.
• Else, display all the tag using for loop

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Quick Answer: How To Read Css

CSS Introduction CSS stands for Cascading Style Sheets. CSS describes how HTML elements are to be displayed on screen, paper, or in other media. CSS saves a lot of work. It can control the layout of multiple web pages all at once. External stylesheets are stored in CSS files.

How can I check my CSS?

Testing Simple CSS Updates with Developer Tools If you are using Google Chrome, navigate to File > View> Developer > Developer Tools. If you are using Safari you will need to activate the Develop Menu by selecting the check box in Safari’s Advanced preferences, then navigate to Develop > Show Web Inspector.

How does the browser read CSS?

The browser will parse the HTML and create a DOM from it, then parse the CSS. Since the only rule available in the CSS has a span selector, the browser will be able to sort the CSS very quickly! It will apply that rule to each one of the three s, then paint the final visual representation to the screen.

How do you explain CSS?

Cascading Style Sheets (CSS) is a stylesheet language used to describe the presentation of a document written in HTML or XML (including XML dialects such as SVG, MathML or XHTML). CSS describes how elements should be rendered on screen, on paper, in speech, or on other media.

How do you comment in CSS?

How to Comment in CSS. To comment in CSS, simply place your plain text inside /* */ marks. This tells the browser that they are notes and should not be rendered on the front end.

How do you do CSS?

Follow the following steps for applying for CSS Exam: Deposit the exam fee in the nearest Govt. Fill in the ‘Online Application Form’ on the official website of FPSC. Dispatch the hard-copy of the online form along with copies of your documents and bank-receipt to the FPSC headquarter, Islamabad.

Should you unit test CSS?

Catch Output Errors Quickly This could impact our CSS output, which we might not notice right away. Having the unit tests in place will help catch output errors before our code is sent to production and will allow us to debug those errors faster if the library changes.

What is debugging CSS?

Quick summary ↬ Debugging in CSS means figuring out what might be the problem when you have unexpected layout results. Debugging — regardless of the language — is never a favorite task. CSS, like other languages, becomes easier to debug when you take time to learn a bit about its quirks.

How do I know if CSS is loaded?

When is a stylesheet really loaded? listen to link.onload. listen to link.addEventListener(‘load’) listen to link.onreadystatechange. setTimeout and check for changes in document.styleSheets. setTimeout and check for changes in the styling of a specific element you create but style with the new CSS.

Does CSS read top down?

The foundation of writing efficient CSS is knowing how browsers parse selectors. The common assumption is that CSS is parsed from left-to-right just as we read English. In reality, browsers use bottom-up parsing for enhanced efficiency, which in plain language means your selectors are read from right-to-left.

How is CSS used in HTML?

CSS is used for defining the styles for web pages. It describes the look and formatting of a document which is written in a markup language. It provides an additional feature to HTML. It is generally used with HTML to change the style of web pages and user interfaces.

Where do you put CSS in HTML?

How to Add CSS to HTML Inline CSS: Requires the style attribute placed inside an HTML element. Internal CSS: Requires the element placed inside the head section of an HTML file. External CSS: Requires the element placed inside the head section of an HTML file.

Is CSS a language?

CSS is the language for describing the presentation of Web pages, including colors, layout, and fonts. It allows one to adapt the presentation to different types of devices, such as large screens, small screens, or printers. CSS is independent of HTML and can be used with any XML-based markup language.

Is learning CSS easy?

CSS is an easy programming language to learn at a basic level. The CSS technology was designed to be accessible so anyone could create their own styled web pages on the internet. A lot of the syntax you see in CSS will be very familiar when you learn the basic concepts of HTML.

What do you learn in CSS?

Here’s what you’ll learn: Box Model. Everything displayed by CSS is a box. Selectors. To apply CSS to an element you need to select it. The cascade. Sometimes two or more competing CSS rules could apply to an element. Specificity. Inheritance. Color. Sizing Units. Layout.

How do I center a div?

To center a div horizontally on a page, simply set the width of the element and the margin property to auto. That way, the div will take up whatever width is specified in the CSS and the browser will ensure the remaining space is split equally between the two margins.

How do I comment in SCSS file?

Comments in SCSS work similarly to comments in other languages like JavaScript. Single-line comments start with // , and go until the end of the line. Nothing in a single-line comment is emitted as CSS; as far as Sass is concerned, they may as well not exist.

How do you comment multiple lines in CSS?

The /* */ comment syntax is used for both single and multiline comments. There is no other way to specify comments in external style sheets.

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