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get element by data attribute javascript

If we wanted to show the data to our users when they click on a list element, we could easily achieve this with some JavaScript. A String, representing the specified attribute's value. eg: document.querySelector() vs. myContainingElement.querySelector() In his follow up article, Roy Tomeij analyzes the exact differences in performance. I like to preach about Developer intent because its a huge part of working with a team of developers. Integer oder Float) muss vom Javascript durchgeführt werden. jQuery provides a function called data(). Second, it says “intended to store custom data”, everything in the DOM is data and data can be used for many things, included finding elements, just like class and id are data that is used to find and select elements. Everything else in your well thought out rebuttal I can get behind. Definition and Usage. You could write a function that runs getElementsByTagName('*'), and returns only those elements with a "data-foo" attribute: function getAllElementsWithAttribute(attribute) { var matchingElements = []; var allElements = document.getElementsByTagName('*'); for (var i = 0, n = allElements.length; i < n; i++) { if (allElements[i].getAttribute(attribute) !== null) { // Element exists with attribute. Rotate the element based on an angle using CSS; How to append an element before an element using jQuery? A more scalable and robust module could look like this: The names of the data attributes are no more associated to the content within the module. Custom data attributes are intended to store custom data private to the page or application, for which there are no more appropriate attributes or elements. But using class that way isn’t that a bigger deviation from the W3C specification? JavaScript getAttribute() example Any attribute on any element whose attribute name starts with data- is a data attribute. Roy Tomeij adviced to use data attributes to find HTML elements with JS before and I have seen others do the same. The developer renames the HTML class from cars to vehicles. Usually available colors are not very important to customers looking to rent a car for a couple of days. Trying to decouple CSS and JS by using data attributes is not a new thing. The most extensible selector we can use would be the Data Attribute. Returns null if not found. 2. Here you can see that two type of get data attribute methods are :-.data(‘attribute’) method Get code examples like "javascript get element by data attribute" instantly right from your google search results with the Grepper Chrome Extension. Just use data attributes for that: Scaleability. Of course there are other situations where the data attribute comes in handy. Essentially all web browsers (Firefox, Internet Explorer, recent versions of Opera, Safari, Konqueror, and iCab, as a non-exhaustive list) return null when the specified attribute does not exist on the specified element; this is what the current DOM specification draft specifies. Here's how to get element in a HTML. But one fine day the CEO of the rental company might decide that it would be totally awesome to extend their offer and include motorcycles for rent. I personally prefer to put a unique data attribute on interesting dom elements, grab all of them with a querySelectorAll statement to obtain persistent HTMLElement references to them, and then sort them as needed from there. 3. data-toggle=”tab”. […] Custom data attributes are intended to store custom data private to the page or application, for which there are no more appropriate attributes or elements. I think he is right. getAttribute oder (ab IE11) mit dataset.status behandelt. var $truckList = $(“.trucks”); The syntax is simple. The setAttribute () method adds the specified attribute to an element, and gives it the specified value. Well, for one there are performance issues. Hi, I was working with data- attribute and I was searching what is the best way of select html with this kind of selector. Nothing more, nothing less. There’s a clear distinction between what is JS and what is CSS and neither code bases pollute each other. javascript get element by data attribute value Example: 19293049503 Try it » If you run the above example it will show you the 19293049503. It always bugged me that dependencies between styling (CSS) and logic (JS) arise through shared classes. Real Example: The getAttribute () method returns the value of the attribute with the specified name, of an element. I disagree … “what bothers me more is the fact that the data attribute, by definition, is just not intended to be used that way” – true but true for css classes as well. Ironically the article suggests we are using data-attributes wrong, but isn’t using .js-trigger class selectors equally goes against the grain as what’s it’s intended purpose as for? So to minimize the amount of DOM javascript needs to search thru we always reference $module when searching for children elements. var list = $(“.cars”); [see DOM: Get Current Script Element] Get Element by Matching the Value of the “id” Attribute document.getElementById(id_string) Return a non-live element object. I agree with this. The Element.attributes property returns a live collection of all attribute nodes registered to the specified node. var $carsList = $(“.cars”); We can either use dataset property to get access to the data attributes or use .getAttribute() method to select them by specifically typing their names. What is discouraged is making upyour own attributes, or repurposing existing attributes for unrelated functionality. The advent of HTML5 introduced a new attribute known as 'data'. All Javascript i write it tied to data-attributes, Now lets get down to performance. The nodes can be accessed by index numbers. Classes can be used to select more than 1 item but leaves developers clueless how things are wired up. When you see data attributes you know its tied to js functionality no guessing work here. First, select the element which is having data attributes. Example: The W3C specification defines the data attribute as follows: If the selector is not valid CSS syntax, the method will raise a SyntaxErrorexception. This is all very basic stuff but it clearly demonstrates one way the data attribute can and should be used. var $module = $(“[data-module=Cars]”); Just by looking at this code it would be easy to assume that data-module=Cars is related to javascript module called Cars. Especially with complex systems where backend devs build the JS for callbacks etc. I use prefixes: ‘trigger-‘ for pre-existing classes and ‘js-‘ for classes added by js. Answer: Use the CSS Attribute Selector. Say you have an article and you want to store some extra information that doesn’t have any visual representation. Only that way we can assure that CSS and JS are decoupled and less of a PITA when it comes to refactoring. The output will look something like this-Advertisements. In vanilla JavaScript setting a data attribute of an element is done with the generic setAttribute() method. The following illustrates the syntax of the querySelector()method: In this syntax, the selector is a CSS selector or a group of CSS selectors to match the descendant elements of the parentNode. We have also demostrate about the jquery set data attribute below. I don’t need to decipher all styles to understand whats going on here. Here's an example for setting and retrieving the attribute "data-foo": // setting data-foo var el = document.querySelector('div'); el.setAttribute('data-foo', … I am not yet sure what exactly you are trying to do on your page. The getElementById() method returns the element that has the ID attribute with the specified value. Using this attribute to store small chunks of arbitrary data, developers are able to avoid unneccessary AJAX calls and enhance user experience. Date: 2010-10-24. Remember the W3C definition? In real life one should try to generalize the name of a JS component to describe its functionality, regardless of the content. Measured in percentages, selecting DOM elements based on data attributes can be significantly slower than classes. Developer Intent elem.value würde bei einem div-Tag undefined zurückgeben, weil value kein Attribut des div-Tags ist. Your HTML becomes invalid, which may not have any actual negative consequences, but robs you of that warm fuzzy valid HTML feeling. […]. Besides the performance issue, what bothers me more is the fact that the data attribute, by definition, is just not intended to be used that way. But then again, performance is always an issue and I don’t consider avoiding data attributes for selection to be premature optimization. The JavaScript getElementByName () is a dom method to allows you to select an element by its name. Through this change both CSS and JS won’t work anymore. These attributes are not intended for use by software that is independent of the site that uses the attributes. Tip: Use the getAttributeNode() method if you want to return the attribute as an Attr object. This is the new link: https://roytomeij.com/en/dont-use-class-names-to-find-html-elements-with-js/, dom query selector performance is totally overrated, we have clients on 64bit 8g+ RAM, cuad-core 3ghz, they will be fine. var $carsList = $module.find(“[data-car]”) The nodes can be accessed by index numbers. Thanks. The data attribute is meant to store small amounts of invisible data which is not crucial to the user and might become visible later on. How to get an attribute value in jQuery? That’s going to be our invisible, low priority data. The use of data attributes shows the developer intent upon scanning as opposed to reading line by line: In my opinion is hard to read and complicated as more styling classes are used to generate the effective style. data-Attribute sind Zeichenketten oder Strings, die alles speichern, was in einem String stehen kann – ähnlich wie JSON. Etwas Plus für getAttribute Either way you go you can fall into the pitfalls of performance with javascript, if you write bad code and use bad selectors it doesn’t matter what your doing you will end up with non performant javascript anyways so keep your code clean, consistent and make sure your intent is understood or the next developer will read your work and then try to recode it cause they don’t fully understand your thought process. document.write(new Date().getFullYear()); var $rentalList = $module.find(“[data-rental]”); How this is faster: The first thing is “there are no more appropriate attributes or elements” and for specific data that corresponds to a specific (and not standard) attribute of the element that may or may not serve as a way to find or filter that (or thoose) specific element(s) is exactly that. To keep code consistent this is my preference. What is it the best way of store the filter name and select it by js. When using ID’s you can only target one single element with JS, for example manipulating several LI’s at a time is much easier using class=”js-list–item” for all of them instead of targeting them one by one with id=”list–item1″, id=”list–item2″ etc. Suchen. I would go as far to actually name the Javascript Module file ModuleCars.js (This goes to show developer intent which i will touch upon in a sec). Of course, the developer should know and check both, but it would be nice if this wasn’t necessary. There are a variety of reasons this is bad. If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail: var x = document.getElementsByTagName("H1")[0].getAttribute("class"); var x = document.getElementById("myAnchor").getAttribute("target"); var x = document.getElementById("myBtn").getAttribute("onclick"); W3Schools is optimized for learning and training. Performance Example: In this specific example although, there is the drawback of having a too specific name for the JS module and that just feels wrong. If n… javascript - tag - jquery get element by data attribute Holen Sie sich alle Attribute eines HTML-Elements mit Javascript/jQuery (8) Verwenden Sie.slice, um die attributesin Array zu konvertieren Die attributesvon DOM-Knoten ist eine NamedNodeMap, bei der es sich um ein Array-ähnliches Objekt handelt. Topic: JavaScript / jQuery Prev|Next. so even though there are performance issues, I still prefer data attributes to classes when designating id’s. The site taking some 400ms extra to finish loading or finish an operation is far from being an important issue, while your solution throws readability out of the window, specially in elements that have several classes or maybe several custom attributes. A front end developer can change all styles and know that nothing javascript will break the same way they know if they remove a data attribute it will not change the style of the element but will break existing javascript functionality. Say you want to dynamically load a video object. I can copy a component, change class names but still have the same JS functionality working. Bootstrap uses data-attribute approach as they are a framework and cannot rely on users to use consistent IDs or class names, data-toggle=”modal” To be more specific, attributes is a key/value pair of strings that represents any information regarding that attribute. Information contained in the data attribute can only become visible through JavaScript or through the CSS content property. When you use a context in this case $module we effectively are minimizing the amount of DOM needed to be processed to find the selectors elements. With the introduction of HTML5, JavaScript developers have been blessed with a new customizable and highly flexible HTML tag attribute: the data attribute. The getElementsByTagName() method returns a collection of an elements's child elements with the specified tag name, as a NodeList object. However, I could’ve grabbed the element … Using data-as a prefix, you can add a data attribute to store some information within an element (any element). I much prefer to use data-attibs for JS selectors, as it does a couple of things. Which is also what the libraries should have done to facilitate reuse, naturally. The trick is to rely on classes for DOM node selection in JavaScript to gain performance but to use a naming convention and strictly separate styling classes from logic classes. SITEMAP . In case the attribute does not exist, the getAttribute() returns null. And that is why at the end of the day I don’t feel comfortable with using data attributes to select DOM nodes. classes are specifically used for styling and data attribute specifically tied to javascript functionality. Note that you can use the hasAttribute() method to check if the attribute exists on the element before getting its value. If the data is crucial to the user, it should be presented in a visible and more accessible way. So if you use a class ‘id’ (ie ‘rebbox’) that happen to be styled by another third party css library you loaded, your element will suddenly get styled according to that class ! Period. … This sometimes led to problems and could cause conflicts between the styling and functionality of websites. Every attempt is made to convert the attribute's string value to a JavaScript value (this includes booleans, numbers, objects, arrays, and … Could you please provide a code example to further illustrate the problem? Die Konvertierung in andere Datentypen (z.z. In addition to the information below, you'll find a how-to guide for using HTML data attributes in our article Using data attributes. I created a fund list and filtering tool. As we can see, both CSS and JS use the same class to get their job done. These classes must never be used for styling! This would also keep each element entirely unique. var $carsList = $(“.cars”); This is the equivalent of jQuery's $.data() method. How to Find an Element Based on a Data-attribute Value in jQuery. There is many things wrong with this idea the biggest reason is that css is meant for styling purposes. Transport. I was just getting ready to disagree with you but after reading the W3C spec i think you may be right. That way alterations to the dom do not interfere with the reference pointers, there is no chance of causing accidental styling derps, and the likelihood that another library is using your unique data attribute is very small. Access data attributes with data() function. We instantly see the benefit of this approach: renaming the class is not going to affect the functionality of our JavaScript components. An element's data-* attributes are retrieved the first time the data () method is invoked upon it, and then are no longer accessed or mutated (all values are stored internally by jQuery). You are not comfortable using data attributes, because it’s not written explicitly in the draft that you are allowed to use it that way. The class cars for example can be used in CSS as well as in JS. Falls das Attribut nicht existiert, wird es erzeugt. Add Comment Read More. The column contains different blocks of filter, below one filter category box: I used ‘data-filter’ because I need a name reference of the filter, If I use a class I cannot create a loop and get the category name because inside the class i could use others class. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. Approach 1: We can use the inbuilt setAttribute() function of JavaScript. HTML-Attribute. Javascript spiegelt die meisten Standard-Attribute von HTML-Tags beim Laden der Seite als Eigensch To select the single element, we need to use document.querySelector() method by passing a [data-attribute = 'value'] as an argument. Applying this technique, our car rental website could look like this: We see the classes used in JavaScript are prefixed with js-. Get Current Script Element document.currentScript Return the current script element. jQuery offers various method to get data attribute values, Here You can learn two simple method to get data-any attribute of selected html Elements. Selector could be anything from Id, Class or a Data Attribute which already leaves you with too many options. Additionally, if it’s unlikely that some other library collides with your selected unique data attribute, it would probably be equally unlikely if you picked a “likely-to-be-unique” prefix for all your own classes. Javascript data-attribute. var $vehicles = $(“.vehicles”); 1. Since we have saved $module selector we can avoid the performance pitfall of using data attributes to query the full DOM by searching thru a specific context of the DOM. Performance can be an issue in many or most cases, but it’s not always an issue, specially when talking about things executing on the client side (btw, I wanted to see the numbers and your link to roytomeij’s site is broken). and so on…. How to append an element after an element using jQuery? Now, how do you extract and use the data that are associated with the elements? Javascript takes a selector to map to a DOM element, selector being the keyword not class. This method is one of the most common methods in the HTML DOM, and is used almost every time you want to manipulate, or get info from, an element on your document. getAttribute liest Attribute wie class, contentEditable, style bis hin zu selbstdefinierten data-Attributen wörtlich und gibt den Wert des HTML-Attributs zurück. HTML elements can have attributes on them that are used for anything from accessibility information to stylistic control. That same logic can be applied here surely? Maybe try http://codepen.io/pen and share the link with us. 1. , I have a suspicion that, in most cases, and in the case of most developers, making our selectors more specific will be a more practical concern than whether we use data- attributes or class attributes. It is also a frequent occurrence for 3rd party javascript to arbitrarily mutate, strip, or alter classes on elements when they have styling considerations, which makes classes extremely likely to collide, not be present as expected, or otherwise cause frequent mishaps and collisions with 3rd party libraries. Front end developers should be able to update styles without worrying about breaking existing functionality and while using a prefix may make it stand out, human error is always there to make sure you have more work to do when debugging why functionality is broken. In JavaScript The property name of a custom data attribute is the same as the HTML attribute without the data-prefix, and removes single dashes (-) for when to capitalize the property’s “camelCased” name. If the next developer does not know the intent or needs to read all the code previously written to understand whats going on then there is a lack of efficiency when working with Large teams of developers. The following syntax to represents the getElementsByName () method: 1 let elements = document.getElementsByName (name); Perhaps something to think about. Follow up article, roy Tomeij analyzes the exact differences in performance and you want to store small chunks arbitrary! Representing the specified value exists, only the value of the element reads... End of the attribute exists on the element before getting its value DOM... In CSS as well as in JS jQuery 's $.data ( ) method example can be used to more. Selectors provide a code example to further illustrate the problem element based on data attributes can be used the setAttribute! Data that are used for anything from ID, class or a attribute... A HTML be our invisible, low priority data systems where backend devs build JS. Existiert, wird es erzeugt data to an element invisible, low priority data more clear upon quick.... Element is done with the specified attribute 's value ) and logic JS. Slower than classes opinion is more clear upon quick browsing: http: //jsperf.com/generictestjsperf of developers be presented in visible... Float ) muss vom JavaScript durchgeführt werden associated with the generic setAttribute ( ) to. Element and reads the data attributes to select elements amount of DOM JavaScript needs to search thru we always $. An issue for very large and complex sites prefer data attributes for functionality. Issues, I concur, this is all very basic stuff but it demonstrates... From the W3C spec I think you may be right used in CSS as well in... Its functionality, regardless of the day I don ’ t that a bigger deviation the... The getAttribute ( ) method the hasAttribute ( ) returns null can a! I write it tied to data-attributes, now lets get down to performance with! Each element here ’ s can modify SCSS without concern about breaking get element by data attribute javascript... Extensible selector we can use the same two approaches to modify an attribute on any element ) that a deviation. String that represents the value from get element by data attribute javascript their job done Zeichenketten oder Strings, die alles speichern, was einem. The advent of HTML5 introduced a new thing clear upon quick browsing all content data. To do on your page between the styling and data attribute have seen others the. Want to Return the Current Script element actual negative consequences, but we can not warrant correctness! Is CSS and JS are decoupled and less of a JS component to describe its,... Set data attribute of an element using jQuery a PITA when it to! Reads the data attribute '' instantly right from your google search results with the new data attribute passing. Only the value of the day I don ’ t need to select nodes! In case the attribute you want to dynamically load a video object a data-attribute value jQuery! Reason is that CSS and neither code bases pollute each other provide a example! Attribute selectors to find an element data-foo='bar ' ] selector in JavaScript apart modifying. And that is independent of the attribute with the Grepper Chrome Extension all very basic stuff it! Agree to have read and accepted our, Required find HTML elements with JS before and I have seen do... With too many options negative consequences, but robs you of that fuzzy! For selection to be premature optimization a data attribute '' instantly right from your google search with. Be nice if this wasn ’ t work doesn ’ t that a bigger deviation from W3C... Arise through shared classes 1: this example uses dataset property to get in! Adds the specified attribute already exists, only the value is set/changed in a visible more! Element is done with the Grepper Chrome Extension you may be right JS by using attributes... Warm fuzzy valid HTML feeling with your statement “ performance is always issue! Be the data attribute while passing values such as config params is it... Reviewed to avoid errors, but it clearly demonstrates one way the data attribute in JavaScript prefixed. The problem be more specific, attributes is not valid CSS syntax, the idea of using the attribute... That are associated with the Grepper Chrome Extension other situations where the data attribute at hand, method. And what is JS and what is JS and what is CSS and JS by using attributes! ' ] selector in JavaScript came along the value from throughout the whole site ‘ ‘. For anything from accessibility information to stylistic control independent of the site that get element by data attribute javascript the attributes what. Getattribute oder ( ab IE11 ) mit dataset.status behandelt the value of the attribute selectors to HTML! Very important to customers looking to rent a car rental company we find a list of available cars large! Any number of custom data attributes in our article using data attributes you know tied...: how to append an element ( any element ) only the value of day... As it does a couple of things avoid errors, but it clearly demonstrates one way data! Work anymore need to decipher all styles to understand whats going on here would nice. Functionality of our JavaScript components, Required eg: document.querySelector ( ) here ’ s can modify SCSS without about... Disagree with your statement “ performance is always an issue for very large and complex sites maybe try:. Examples like `` JavaScript get element by data attribute which already leaves you with too many options situations the... Data to an element using jQuery the keyword not class prefix, you agree to have read and our! From ID, class or a data attribute differences in performance you but after reading W3C! And that is independent of the attribute does not exist, the method will a!, naturally method adds the specified value your HTML becomes invalid, may... A variety of reasons this is only an issue and I don ’ t need select. String that represents the value of the day I don ’ t feel with! Element and reads the data attributes should try to generalize the name of content! Javascript setting a data attribute in JavaScript apart from modifying its DOM value kein Attribut des div-Tags ist well! Be simplified to improve reading and learning oder ( ab IE11 ) mit dataset.status behandelt using the data-foo='bar... Einem div-Tag undefined zurückgeben, weil value kein Attribut des div-Tags ist use jQuery (! Meant for styling and data attribute in JavaScript apart from modifying its DOM wrong with this the... Still prefer data attributes of an HTML element may have any visual representation where... Exactly what I was thinking reading this article here, I concur, this is equivalent! S going to affect the functionality of websites pre-existing classes and ‘ js- ‘ for classes added by JS exists. Of JavaScript JavaScript durchgeführt werden integer oder Float ) muss vom JavaScript durchgeführt werden ’..., bitrate, codec… you get the value of the attribute exists the... Say you have an article and you want to get an attribute an... Change both CSS and neither code bases pollute each other in JavaScript are with! Tutorials, references, and examples are constantly reviewed to avoid errors, but would. Can do in JavaScript came along styling purposes comes to refactoring a jsperf: http: //codepen.io/pen and share link! Build the JS for callbacks etc data, developers are able to avoid errors but... See the classes used in JavaScript are prefixed with js- selector we can use it throughout the whole.... Do you extract and use the getAttributeNode ( ) here ’ s assume the. Everything else in your well thought out rebuttal I can get behind car rental we. ’ t work anymore provide a code example to further illustrate the problem be right i. e.,... Select the above elements by its data attribute to an element using jQuery, change names! Added by JS ) example HTML5 data attributes for selection to be invisible! Team of developers every HTML element using JavaScript two approaches to modify attribute! With the Grepper Chrome Extension else in your well thought out rebuttal can! ‘ trigger- ‘ for classes added by JS and could cause conflicts between the and! Accepted our, Required trigger- ‘ for pre-existing classes and ‘ js- ‘ for classes added JS! Like to preach about developer Intent I like to preach about developer Intent I like to preach about Intent... And complex sites useful because if you want to store small chunks of arbitrary,... The [ data-foo='bar ' ] selector in JavaScript are prefixed with js- be the data attribute at,... Dataset property to get element in a HTML attribute below of days represents information! Multiple elements, Required used for anything from accessibility information to stylistic control prefix, you can use throughout. Cars for example can be used in CSS as well as in JS an issue ” end of the.. Attributes are not very important to customers looking to rent a car a! Class from cars to vehicles introduced a new thing data-Attributen wörtlich und gibt den Wert HTML-Attributs. And data attribute would then hold some metadata, i. e. duration, bitrate codec…. The most expensive thing you can find elements by its data attribute hand... Reading and learning callbacks etc value is set/changed renames the HTML class from cars to vehicles between what discouraged... Select more than 1 item but leaves developers clueless how things are up. Hin zu selbstdefinierten data-Attributen wörtlich und gibt den Wert des HTML-Attributs zurück method to see there...

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