Wait 5 seconds before executing next line
You have to put your code in the callback function you supply to setTimeout: Any other code will execute immediately.
javascript
map function for objects (instead of arrays)
There is no native map to the Object object, but how about this: Run code snippet But you could easily iterate over an object using for … in: Run code snippet Update A lot of people are mentioning that the previous methods do not return a new object, but rather operate on the object itself. For that matter I wanted … Read more
What does href expression do?
An <a> element is invalid HTML unless it has either an href or name attribute. If you want it to render correctly as a link (ie underlined, hand pointer, etc), then it will only do so if it has a href attribute. Code like this is therefore sometimes used as a way of making a link, but without having to provide an actual … Read more
How to format a JavaScript date
For custom-delimited date formats, you have to pull out the date (or time) components from a DateTimeFormat object (which is part of the ECMAScript Internationalization API), and then manually create a string with the delimiters you want. To do this, you can use DateTimeFormat#formatToParts. You could destructure the array, but that is not ideal, as … Read more
How do I color a hexagonal grid such that it doesn’t have neighbors of the same color?
In a hex grid you’ll need three colors to color each hex so that it doesn’t have the same color as a neighbor: You were on the right track with your solution. Instead of adding x+y you’ll want to subtract x-y. The other change is that &3 is for bit manipulation; you’ll want %3 instead. … Read more
JavaScript document.getElementById().value logs empty value
Ensure to add an event handler. Add an onchange event listener to input element.
How do I check if an array includes a value in JavaScript?
Modern browsers have Array#includes, which does exactly that and is widely supported by everyone except IE: Run code snippet You can also use Array#indexOf, which is less direct, but doesn’t require polyfills for outdated browsers. Run code snippet Many frameworks also offer similar methods: jQuery: $.inArray(value, array, [fromIndex]) Underscore.js: _.contains(array, value) (also aliased as _.include and _.includes) Dojo Toolkit: dojo.indexOf(array, value, [fromIndex, findLast]) Prototype: array.indexOf(value) MooTools: array.indexOf(value) MochiKit: findValue(array, value) MS … Read more
“Uncaught SyntaxError: Cannot use import statement outside a module” when importing ECMAScript 6
I’m using ArcGIS JSAPI 4.12 and wish to use Spatial Illusions to draw military symbols on a map. When I add milsymbol.js to the script, the console returns error Uncaught SyntaxError: Cannot use import statement outside a module` so I add type=”module” to the script, and then it returns Uncaught ReferenceError: ms is not defined … Read more
addEventListener vs onclick
Both are correct, but none of them are “best” per se, and there may be a reason the developer chose to use both approaches. Event Listeners (addEventListener and IE’s attachEvent) Earlier versions of Internet Explorer implement javascript differently from pretty much every other browser. With versions less than 9, you use the attachEvent[doc] method, like … Read more
ES6 Map in Typescript
EDIT (Jun 5 2019): While the idea that “TypeScript supports Map natively” is still true, since version 2.1 TypeScript supports something called Record. Unfortunately the first generic parameter (key type) is still not fully respected: even with a string type, something like peopleA[0] (a number) is still valid. EDIT (Apr 25 2016): The answer below is old and should not be considered the best answer. … Read more