JavaScript Cheat Sheet

JavaScript often abbreviated as “JS”, is a high-level, dynamic, untyped, interpreted run-time language.It has been standardized in the ECMAScript language specification. Alongside HTML and CSS, JavaScript is one of the three core technologies of World Wide Web content production.

Cheat Sheet for JavaScript:

Expres­sions Syntax

^	Start of string
$	End of string
.	Any single character
(a|b)	a or b
(…)	Group section
[abc]	In range (a, b or c)
[^abc]	Not in range
\s	White space
a?	Zero or one of a
a*	Zero or more of a
a*?	Zero or more, ungreedy
a+	One or more of a
a+?	One or more, ungreedy
a{3}	Exactly 3 of a
a{3,}	3 or more of a
a{,6}	Up to 6 of a
a{3,6}	3 to 6 of a
a{3,6}?	3 to 6 of a, ungreedy
\	Escape character
[:punct:]	Any punctu­ation symbol
[:space:]	Any space character
[:blank:]	Space or tab

JavaScript Dates

Date()	setMonth()
getDate()	setFul­lYear()
getDay()	setHours()
getMonth	setMin­utes()
getFul­lYear	setSec­onds()
getYear	setMil­lis­eco­nds()
getHours	setTime()
getMinutes	setUTC­Date()
getSeconds	setUTC­Day()
getMil­lis­econds	setUTC­Month()
getTime	setUTC­Ful­lYear()
getTim­ezo­neO­ffset()	setUTC­Hours()
getUTC­Date()	setUTC­Min­utes()
getUTC­Day()	setUTC­Sec­onds()
getUTC­Month()	setUTC­Mil­lis­eco­nds()
getUTC­Ful­lYear()	toSource()
getUTC­Hours()	toString()
getUTC­Min­utes()	toGMTS­tring()
getUTC­Sec­onds()	toUTCS­tring()
getUTC­Mil­lis­eco­nds()	toLoca­leS­tring()

JavaScript Arrays

concat()	slice()
join()	sort()
length	splice()
pop()	toSource()
push()	toString()
reverse()	unshift()
shift()	valueOf()

JavaScript Strings

charAt()	slice()
charCo­deAt()	split() x
concat()	substr()
fromCh­arC­ode()	substr­ing()
indexOf()	toLowe­rCase()
lastIn­dexOf()	toUppe­rCase()
length	toLoca­leL­owe­rCase()
locale­Com­pare()	toLoca­leU­ppe­rCase()
match() x	toSource()
replace() x	valueOf()

JavaScript Functions

decode­URI()	isNaN()
decode­URI­Com­pon­ent()	Number()
encode­URI()	parseF­loat()
encode­URI­Com­pon­ent()	parseInt()
escape()	String()
eval()	unescape()

JavaScript Booleans

toSource()	valueOf()
toString()

JavaScript Numbers and Maths

abs()	min()
acos()	NEGATI­VE_­INF­INITY
asin()	PI
atan()	POSITI­VE_­INF­INITY
atan2()	pow()
ceil()	random()
cos()	round()
E	sin()
exp()	sqrt()
floor()	SQRT1_2
LN10	SQRT2
LN2	tan()
log()	toSource()
LOG10E	toExpo­nen­tial()
LOG2E	toFixed()
max()	toPrec­ision()
MAX_VALUE	toString()
MIN_VALUE	valueOf()

JavaScript RegExp Object

compile()	lastParen
exec()	leftCO­ntext
global	multiline
ignoreCase	rightC­ontext
input	source
lastIndex	test()

Incrementing /decrementing numbers

Increment	++x or x++
Decrement	–x or x–

The difference is that ++x (–x) returns the incremented (decremented) value, while x++(x–) returns the previous value of x.