The JavaScript exception "character class escape cannot be used in class range in regular expression" occurs when a Unicode-aware regular expression pattern contains a character class where a boundary of a character range is another character class, such as a character class escape.... Examples Invalid cases js /[\s-_]/u; // \s is a character...classes can be nested Valid cases js // Put the hyphen at the start...
Learn about the HTMLInputElement.valueAsNumber property, including its type, code examples, specifications, and browser compatibility.... js const logElement = document....compared to that value as a number. js const logElement = document....
It is very important to consider how you are using JavaScript on your websites and think about how to mitigate any performance issues that it might be causing. While images and video account for over 70% of the bytes downloaded for the average website, byte per byte, JavaScript has a greater potential for negative performance impact — it can significantly impact download times, rendering performance, and CPU and battery usage. This article introduces tips and techniques for optimizing JavaScript to enhance the performance of your website....js"></script> ... </head> This works...rel="preload" href="important-js.js" as="script" /> <!-- Preload...
The content behind MDN Web Docs. Contribute to mdn/content development by creating an account on GitHub....over time to the color value: ```js colorPicker.addEventListener("input"...appropriately in either case. ```js colorPicker.select(); ``` ##...
A literal character specifies exactly itself to be matched in the input text....the Removing HTML tags example: js const pattern = /<.+?>/g; In...when paired with other features: js /^[😄]$/.test("😄"); // false...
Learn about the CompressionStream interface, including its constructor and properties, code examples, specifications, and browser compatibility.... js const compressedReadableSt =...
Learn about the Window.open() method, including its syntax, code examples, specifications, and browser compatibility.... Syntax js open() open(url) open(url, target)...windows. Examples Opening a new tab js window.open("https://www.mozilla...
In the previous Cross browser video player article we described how to build a cross-browser HTML video player using the Media and Fullscreen APIs. This follow-up article looks at how to style this custom player, including making it responsive....browser now needs to be set: js // Display the user defined video...support the <progress> element: js const supportsProgress = document...
So that's it for focus management, and for our app! Congratulations for working your way through all our Vue tutorials. In the next article we'll round things off with some further resources to take your Vue learning further....toggleToItemEditForm() method, like so: js toggleToItemEditForm() { console...the focus() method on the ref. js focusOnEditButton() { const editButtonRef...