the murmurous sea

www.geeksforgeeks.org/difference-between-node-js-require-and-es6-import-and-export/

Events mouseover/mouseout, relatedTarget :These events are special, because they have property relatedTarget If we don’t examine event.target inside the handlers, then it may seem that the mouse pointer left #parent element, and then immediately came back over it. But that’s not the case! The pointer is still over the parent, it just moved deeper into the child element. If there are some actions..

The DOMContentLoaded event fires when the document is loaded and the DOM tree is fully constructed. The load event fires when all subframes, images, stylesheets, scripts, etc have been downloaded. The lifecycle of an HTML page has three important events DOMContentLoaded : the browser fully loaded HTML, and the DOM tree is built, but external resources like pictures and stylesheets may be not yet..

1. Timeouts throttled to ≥ 4ms : In modern browsers, setTimeout()/setInterval() calls are throttled to a minimum of once every 4 ms when successive calls are triggered due to callback nesting (where the nesting level is at least a certain depth), or after a certain number of successive intervals. : In Chrome and Firefox, the 5th successive callback call is clamped; Safari clamps on the 6th call;..

1. The setInterval() function is commonly used to set a delay for functions that are executed again and again, such as animations. You can cancel the interval using WindowOrWorkerGlobalScope.clearInterval(). 2. If you wish to have your function called once after the specified delay, use WindowOrWorkerGlobalScope.setTimeout(). To call a function repeatedly (e.g., every N milliseconds), consider u..

- Use JSON.parse() to parse the response for AJAX. : AJAX works with callbacks, fetch with Promises. Use JSON.parse() to parse the response for AJAX. - Use json() to parse the response for fetch. json.parse() 1. method 2. Synchronous 2. parses a JSON string, constructing the JavaScript value or object described by the string. 3. An optional reviver function can be provided to perform a transform..

includes() String.prototype.includes() : method determines whether one string may be found within another string, returning true or false as appropriate. : Polyfill(method) has been added to the ECMAScript 2015 specification and may not be available in all JavaScript implementations yet. However, you can easily polyfill this method. Syntax str.includes(searchString[, position]) - searchString : ..

"JavaScript는 객체(인스턴스)와 객체 간의 상속 관계를 자유롭게 설정할 수 있습니다." from https://opentutorials.org/module/4047/24626 객체 간의 상속 - JavaScript 객체 지향 프로그래밍 수업소개 JavaScript는 객체(인스턴스)와 객체 간의 상속 관계를 자유롭게 설정할 수 있습니다. 이 수업에서는 클래스가 아닌 객체를 통해서 상속하는 방법을 알아봅니다. 강의1 자바스크립트의 � opentutorials.org instance : An “instance” means a reference to an “object” created by “new” or the equivalent. from https://www.quora.com/What-is-an-..

1. method 2. creates a new, shallow-copied Array instance from an array-like or iterable object. 3. The length property of the from() method is 1. 4. In ES2015, the class syntax allows sub-classing of both built-in and user-defined classes. : As a result, static methods such as Array.from() are "inherited" by subclasses of Array, and create new instances of the subclass, not Array. [Syntax] Arra..

검색어를 칠 때 버튼을 누르고 난 직후에 검색이 되게 하려고 함 keydown은 검색어를 입력한 직후는 앞에 값을 보여줌. 그 다음 문자를 넣어야 전에 입력한 것이 출력됨. keyup은 누름과 동시에 값이 출력됨 왜 그렇지....?? >> because of the firing moment. The key value adds later when I use keydown in the event listener. Because the default comes later than key event. keydown keypress keyup This event has been deprecated, no longer recommended. Use beforeinput or keydown instead. firin..