2017-10-30-javascript-recipes.md

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Javascript recipes

Get the computed style of a html element

getComputedStyle is a function attach to window object. It allows to get the exact same information than the chrome computed properties So the list of all properties of a given element

getComputedStyle($('body'))

To extract only the info you need you can take advantage of ES6 syntax

const {
      order,
      height,
    } = getComputedStyle(el)

So here we got for example order: 0 and height: 25078.3px

To extract only the numerical value of the pixel and drop the .3 You can use

parseInt(getComputedStyle($('body')).height, 10)

The result is 25078

What is copying an object ?

https://medium.com/@tkssharma/objects-in-javascript-object-assign-deep-copy-64106c9aefab

The original

https://scotch.io/bar-talk/copying-objects-in-javascript

Immutability

• https://hackernoon.com/introducing-immer-immutability-the-easy-way-9d73d8f71cb3
• https://github.com/facebook/immutable-js
• https://github.com/mweststrate/immer

False switch case

{% embed url="https://gist.github.com/sinsunsan/bc176b1d845d5f7dc14d63e946b1278d" %}

Conditionally insert some properties in an object

{% embed url="https://medium.com/@mikeh91/conditionally-adding-keys-to-javascript-objects-using-spread-operators-and-short-circuit-evaluation-acf157488ede" %}