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View react-lifecycle-cheatsheet.md

React lifecycle cheatsheet

Method Side effects1 State updates2 Example uses
Mounting
componentWillMount Constructor equivalent for createClass
render Create and return element(s)
componentDidMount DOM manipulations, network requests, etc.
Updating
componentWillReceiveProps Update state based on changed props
View Effective_Engineer.md

FWIW: I didn't produce the content presented here (the outline from Edmond Lau's book). I've just copy-pasted it from somewhere over the Internet, but I cannot remember what exactly the original source is. I was also not able to find the author's name, so I cannot give him/her the proper credits.


Effective Engineer - Notes

What's an Effective Engineer?

View what-forces-layout.md

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Element

Box metrics
  • elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent
  • elem.clientLeft, elem.clientTop, elem.clientWidth, elem.clientHeight
  • elem.getClientRects(), elem.getBoundingClientRect()
View hn_seach.js
function query() {
var
// HN is done with very unsemantic classes.
job_list = Array.prototype.slice.call(document.querySelectorAll('.c5a,.cae,.c00,.c9c,.cdd,.c73,.c88')),
query_list = Array.prototype.slice.call(arguments),
shown = 0, total = job_list.length;
// Traverses up the dom stack trying to find a match of a specific class
function up_to(node, klass) {
if (node.classList.contains(klass)) {