Dictionary

A-Z

Name	Examples
[...array]	var a = [1,2,3,4,5] [...a] //Equal to [1,2,3,4,5]
`Hello ${a}`	var a = "John" //Equal to "Hello John"
abs()	Math.abs(-1.234)
add()	var unique = new Set([1,2,3,4,5])
alert()	alert("happy new year")
acos()	Math.acos(0.4) //Equal to 1.1592794807274085
acosh()	Math.acosh(4) //Equal to 2.0634370688955608
addEventListener()
altkey	function isKeyPressed(event) { if (event.altKey) { document.getElementsByTagName("p")[0].style.color = "#ff0000"; } else { alert("The ALT key was NOT pressed!"); } }
appendChild
appCodeName	navigator.appCodeName
appName	navigator.appName
appVersion	navigator.appVersion
asin()	Math.asin(-0.4) //Equal to -0.41151684606748806
asinh()	Math.asinh(20) //Equal to 3.6895038689889055
assign()	const target = { a: 1, b: 2 }; const source = { b: 4, c: 5 }; const returnedTarget = Object.assign(target, source); console.log(target); // expected output: Object { a: 1, b: 4, c: 5 } console.log(returnedTarget); // expected output: Object { a: 1, b: 4, c: 5 }
atan()	Math.atan(20) //Equal to 1.5208379310729538
atanh()	Math.atanh(0.2) //Equal to 0.2027325540540822
attribute
availHeight	screen.availHeight
boolean? a : b	4===5? true : false //Equal to false
break
cbrt()	Math.cbrt(8) //Equal to 2
ceil()	Math.ceil(2.145) //Equal to 3
charAt(num)	"nop".charAt(1) //Equal to "o"
childNodes	var c = document.body.childNodes; c[0];
clearInterval()	clearInterval(setInterval(alert("Hi")),3000)
click
colorDepth	screen.colorDepth
confirm()	confirm("happy new year")
concat()	[1,2,3,4].concat([5],[6]) //Equal to [1,2,3,4,5,6]
console.log()	console.log("1+2")
const	const a = "apple" //globle
continue
copyWithin()	[1,2,3,4,5].copyWithin(2,1) //Equal to [1,2,2,3,4]
cos()	Math.cos(32) //Equal to 0.8342233605065102
cosh()	Math.cosh(32) //Equal to 39481480091340.34
cost()	Math.cost()
createElement()	var para = document.createElement("p")
createTextNode()	document.createTextNode("This is new.")
close()	window.close()
Date()	var a = new Date()
dblclick
do……while	var i = 0 do{ document.write(i) i++ }while(i<5)
E	Math.E //Equal to 2.718281828459045
endsWith	"happy".endsWith("y") //Equal to true
entries()	arrSet = {a:1,b:2,c:3} Object.entries(arrSet) //Equal to [["a",1],["b",2],["c",3]]
eval()	eval("1+2") //Equal to 3
every()	[1,2,3,4,5].every(x => x<4) //Equal to false
exp()	Math.exp(20) //Equal to 485165195.4097903
fill()	[1,2,3,4,5].fill("h") //Equal to ["h","h","h","h","h"]
find()	[1,2,3,4,5].find(x => x>2) //Equal to 3
findIndex()	[1,2,3,4,5].find(x => x>2) //Equal to 2
flat()	[1,2,3,[4,5]].flat() //Equal to [1,2,3,4,5]
floor()	Math.floor(2.145) //Equal to 2
freeze()	Object.freeze(obj)
forEach()	[1,2,3,4,5].forEach((x,y)=>console.log(y+ "" +x))
for loop	for(i=0; i<6; i++){}
for……in
for……of
from()	Array.from("12") //Equal to ["1","2"]
function(){}	function(){ return "happy new year"; } \\Equal to () => "happy new year"
getElementById(id)	document.getElementById("demo")
getElementsByTagName(name)	getElementsByTagName("p")
getElementsByClassName(name)	getElementsByTagName("demo")
getTime()	new Date().getTime() //Equal to time from 1970.1.1
getFullYear()	new Date().getFullYear() //Equal to 2020
setFullYear()	new Date().setFullYear(2019) //Equal to 2019yr
getUTCFullYear()	new Date().getUTCFullYear() //Equal to 2020
setUTCFullYear()
getMonth()	new Date().getMonth() //Equal to Month -1
setMonth()
getUTCMonth()
setUTCMonth()
getDate()	new Date().getDate() //Equal to today number
setDate()
getNamedItem()	var x = btn.attributes.getNamedItem("class").value
getUTCDate()
setUTCDate()
getDay()	new Date().getDay() //Equal to a week number
setDay()
getUTCDay()
setUTCDay()
getHours()	new Date().getHours() //Equal to this hour number
setHours()
getUTCHours()
setUTCHours()
getMinutes()	new Date().getMinutes() //Equal to this minute number
setMinutes()
getUTCMinutes()
setUTCMinutes()
getSeconds()	new Date().getSeconds() //Equal to this seconds number
setSeconds()
getUTCSeconds()
setUTCSeconds()
getMilliseconds()	new Date().getMilliseconds() //Equal to this milliseconds number
setMilliseconds()
getUTCMilliseconds()
setUTCMilliseconds()
has()
height	screen.height //Equal to screen height
hypot()	Math.hypot(3,4) //Equal to 5
includes()	[1,2,3,4,5].includes(5) //Equal to true
indexOf()	"abcde".indexOf("b") //Equal to 1
Infinity
innerHeight	window.innerHeight //Equal to browser window height
innerHTML
innerWidth	window.innerWidth //Equal to browser window width
insertBefore()	element.insertBefore(para,child);
isArray()	Array.isArray([1,2,3,4,5]) //Equal to true
isFinite	isFinite(10/0)
isInteger()	Number.isInteger(10/2) //Equal to true
isNaN()	isNaN("123") //Equal to false
isSafeInteger()	Number.isSafeInteger("2") //Equal to false
item()	var x = a.attributes.item(1).value
if……else if……	if(x>1){ return true; }else{ return false; }
join()	[1,2,3,4,5].join("") //Equal to "12345"
lang
language	navigator.language
languages	navigator.languages
lastIndexOf()	[1,2,3,4,5].lastIndexOf(5) //Equal to 4
length	[1,2,3].length //Equal to 3
let	let a = "apple" //not global
LN2	Math.LN2 //Equal to 0.6931471805599453
LN10	Math.LN10 //Equal to 2.302585092994046
location.href	location.href="https://www.google.com/"
log()	Math.log(2) //Equal to 0.6931471805599453
LOG2E	Math.LOG2E //Equal to 1.4426950408889634
LOG10E	Math.LOG10E //Equal to 0.4342944819032518
map	[1,2,3,4,5].map(x => x*2) //Equal to [2,4,6,8,10]
match()	"Str".match(/[a-z]/g) //Equal to ["t","r"]
max	Math.max(1,2,3,4,5) //Equal to 5
nextSibling
nextElementSibling
min	Math.min(1,2,3,4,5) //Equal to 1
mousedown
mouseenter
mouseleave
mousemove
mouseover
mouseout
mouseup
moveTo(x,y)
name	var a = btn.atrributes.item(0).name
NaN
nodeName
Number()	Number("12345") //Equal to 12345
Object.values()	const a = { a: 'somestring', b: 42, c: false }; Object.values(a) //Equal to ['somestring', 42, false]
onblur()
onclick()
onerror()
onkeyup()
onkeydown()
onkeypress()
onfocus()
onload()
onmouseover()
onmouseup()
onmousedown()
onunload
onpaste
open()	window.open("https://www.google.com")
onsubmit()
outerHeight	window.outerHeight //Equal to window.innerHeight + bar
outerWidth	window.outerWidth //Equal to window.innerHeight + scroll
padStart	last4Digits.padStart(card.length,"*")
parseInt()	parseInt("2.456") //Equal to 2
parseFloat()	parseFloat("2.456") //Equal to 2.46
pixelDepth	screen.pixelDepth
PI	Math.PI //Equal to 3.14159256
platform	navigator.platform //Equal to System name
pop()	[1,2,3,4,5].pop() //Equal to 5
pow(x,y)	Math.pow(2,3) //Equal to 8
previousSibling
previousElementSibling
print()	window.print()
product	navigator.product
prompt()	prompt("happy new year")
push()	[1,2,3,4,5].push("6") //Equal to [1,2,3,4,5,6]
querySelector()
querySelectorAll()
reduce()	[1,2,3,4,5].reduce((a,b)=>a*b) //Equal to 120
reduceRight()	[1,2,3,4,5].reduce((a,b)=>a-b) //Equal to -5
random()	Math.random() //Equal to range [0-1]
remove()
removeChild
removeEventListener()
removeNamedItem()	btn.attributes.removeNamedItem("value")
repeat(num)	"12".repeat(2) //Equal to "1212"
replace	var a = "Hi World" a.replace("Hi","No") //Equal to "No World"
replaceChild
reverse()	[1,2,3,4,5].reverse() //Equal to [5,4,3,2,1]
round()	Math.round(3.25) //Equal to 3
Set()	var arr = New Set()
setInterval()	setInterval(alert("Hi"),3000) //Equal to alert("Hi") each 3s
setNamedItem()
setTimeout()	setTimeout(alert("Hi"),3000) //Equal to alert("Hi")
shift()	[1,2,3,4,5].shift() //Equal to 1
sin()	Math.sin(30) //Equal to -0.9880316240928618
sinh()	Math.sinh(30) //Equal to 5343237290762.231
slice()	[1,2,3,4,5].slice(1,2) //Equal to [2]
some()	[1,2,3,4,5].some(x => x<2) //Equal to true
sort()	[1,3,2,5,4].sort() //Equal to [1,2,3,4,5]
specified	var btn = document.getElementsByTagName("BUTTON")[0]; var x = btn.getAttributeNode("onclick").specified;
splice()	[1,2,3,4,5].splice(2,1) //Equal to [3]
split()	"1234".split("") //Equal to ["1","2","3","4"]
sqrt()	Math.sqrt(4) // Equal to 2
SQRT2	Math.SQRT2 //Equal to 1.4142135623730951
SQRT1_2	Math.SQRT1_2 //Equal to 0.7071067811865476
startsWith	"12345".startsWith("1") //Equal to true
String()	String(12345) //Equal to "12345"
switch	switch(x){ case 0 : return "happy"; break; }
style.property
tan()	Math.tan(45) //Equal to 1.6197751905438615
tanh()	Math.tanh(-45) //Equal to -1
toFixed()	1.23456.toFixed(3) //Equal to 1.235
toLowerCase()	"Happy".toUpperCase() //Equal to "happy"
toString()	[1,2,3,4,5].toString() //Equal to "1,2,3,4,5"
toString(2)	var a = 2; a.toString(2) //Equal to "10"
toString(8)	var a = 16; a.toString(8) //Equal to "20"
toString(16)	var a = 15; a.toString(16) //Equal to "f"
toUpperCase()	"happy".toUpperCase() //Equal to "HAPPY"
typeof n	typeof includes "number","string","boolean", etc
undefined	var a !== undefined //Equal to false
unshift()	[1,2,3,4,5].unshift(6) //Equal to [6,1,2,3,4,5]
userAgent	navigator.userAgent
value	var a = btn.atrributes.item(0).value
var	var a = "apple" //global
wheel
while
width	screen.width //Equal to screen width
window	window.innerWidth //Equal to browser width
write()	document.write("happy new year")
writeIn()	document.writeIn("happy new year")
+	1+2 //Equal to 3
-	1-2 //Equal to -1
*	1*2 //Equal to 2
/	1/2 //Equal to 0.5
**	2**2 //Equal to 4
%	2%1 //Equal to 0
++	2++ OR ++2
--	2-- OR --2
>=	x>=4
~	~5
^
>	x>4
<	x<4
<=	x<=4
<<
>>
>>>
&
&&	true && true //Equal to true
|
||	true || false //Equal to true
!=	true != false //Equal to true
!==	true !== false //Equal to ture
==	4=="4" //Equal to true
===	4==="4" //Equal to false