Cheat

XmlHttpRequest

const req = new XMLHttpRequest();
req.open("GET", "url", true);
req.send(null);
console.log(req.responseText);

* req.onreadystatechange = function(){console.log("ready")}
* req.readyState  // === 4 (request finished)
* req.status  // === 200 (response received)
* req.(setRequest|getResponse)Header()

history (window.history)
- pushState(history.state, “title”, “http://url”)
- back()
- foward()
- go(1) && go(-1)
- length
Save

window.document.execCommand("saveAs", true, "test.txt")

Scroll to bottom of page (dynamically appending content)

<body id='body' onLoad='main()'>
    <div id="top"></div>
    <div id="bottom"></div>
</body>
<script>
    document.getElementById('bottom').scrollIntoView();
</script>

Change url :
- Load page on click
```
<input id="btntest" type="button" value="Check"
onclick="window.location.href = 'http://www.google.com'" />
```
- window.open(url) # open url in new tab
- window.navigate("index.html") # open url same tab (navigate)
- document.location.replace("index.html") # open url same tab (replace)
- window.location.href # url
- window.location.hostname # domain name
- window.location.pathname # path and filename of current page
- window.location.protocol # protocl (http:)
- window.location.assign # load document
Get info
- window.navigator -> dict full of info
- window.status -> chang status bar of browser : connection received ;..
- window.origin -> get the url origin of myself
Passing additional parameters to a Promise .then P.then( doWork.bind(‘text’, null) ); P.then( function(data) {return doWork(‘text’, data);} ); P.then( data => doWork(‘text’, data) );

Idioms

Run other thread setTimeout(func, 0)
Global (The correct way) window.myglobal = 3;

Vars

keyword	meaning
var	function
let	block
const	constant
[]	global
window.	global

Loop

Range: Loop 100 times

for (let i of Array(100).keys()) {
    console.log(i);
}

Array

var a = [1, 2, 3]

String

Substring
RegExp
unescape("hello%20world")
substr(from, length)
substring(from, to)

var str = "Hi";  
var res = str.substring(1,4)  
var res = str.substring(-3)

Number

To Hex

var d = 16;
var s = d.toString(16);
var d = parseInt(s, 16);

Regex

var str = "Visit W3Schools!";
var n1 = str.search("W3Schools");
var n2 = str.search(/w3schools/i);
var res = str.replace(/w3schools/i, "Microsoft");

Nodejs

process.version process.versions

Object

var o = {1:2, "toto":3}
Object.keys(o).length
var a = 1; window['a'];
for (var prerty in obj){}