| JavaScript Arrays |
| concat() |
Join several arrays into one |
| copyWithin() |
Copy array elements within the array, to and from specified positions |
| indexOf() |
Return the primitive value of the specified object |
| includes() |
Check if an array contains the specified element |
| join() |
Combine elements of an array into a single string and return the string |
| entries() |
Return a key/value pair Array Iteration Object |
| every() |
Check if every element in an array passes a test |
| fill() |
Fill the elements in an array with a static value |
| filter() |
Create a new array with every element in an array that pass a test |
| find() |
Return the value of the first element in an array that pass a test |
| forEach() |
Call a function for each array element |
| from() |
Create an array from an object |
| lastIndexOf() |
Give the last position at which a given element appears in an array |
| pop() |
Remove the last element of an array |
| push() |
Add a new element at the end |
| reverse() |
Sort elements in descending order |
| reduce() |
Reduce the values of an array to a single value (going left-to-right) |
| reduceRight() |
Reduce the values of an array to a single value (going right-to-left) |
| shift() |
Remove the first element of an array |
| slice() |
Pull a copy of a portion of an array into a new array object |
| sort() |
Sort elements alphabetically |
| splice() |
Add elements in a specified way and position |
| unshift() |
Add a new element to the beginning |
| JavaScript Boolean Methods |
| toString() |
Convert a Boolean value to a string, and return the result |
| valueOf() |
Return the first position at which a given element appears in an array |
| toSource() |
Return a string representing the source code of the object |
| JavaScript Arithmetic Operators |
| + |
Addition |
| - |
Subtraction |
| * |
Multiplication |
| / |
Division |
| (...) |
Grouping operator (operations within brackets are executed earlier than those outside) |
| % |
Modulus (remainder) |
| ++ |
Increment numbers |
| -- |
Decrement numbers |
| == |
Equal to |
| === |
Equal value and equal type |
| != |
Not equal |
| !== |
Not equal value or not equal type |
| > |
Greater than |
| < |
Lesser than |
| >= |
Greater than or equal to |
| <= |
Lesser than or equal to |
| ? |
Ternary operator |
| Logical Operators |
| && |
Logical AND |
| || |
Logical OR |
| ! |
Logical NOT |
| Bitwise Operators |
| & |
AND statement |
| | |
OR statement |
| ~ |
NOT |
| ^ |
XOR |
| << |
Left shift |
| >> |
Right shift |
| >>> |
Zero fill right shift |
| Functions |
| alert() |
Output data in an alert box in the browser window |
| confirm() |
Open up a yes/no dialog and return true/false depending on user click |
| console.log() |
Write information to the browser console (good for debugging purposes) |
| document.write() |
Write directly to the HTML document |
| prompt() |
Create a dialog for user input |
| Global Functions |
| decodeURI() |
Decode a Uniform Resource Identifier (URI) created by encodeURI or similar |
| decodeURIComponent() |
Decode a URI component |
| encodeURI() |
Encode a URI into UTF-8 |
| encodeURIComponent() |
Same but for URI components |
| eval() |
Evaluate JavaScript code represented as a string |
| isFinite() |
Determine whether a passed value is a finite number |
| isNaN() |
Determine whether a value is an illegal number |
| Number() |
Convert an object's value to a number |
| parseFloat() |
Parse a string and return a floating point number |
| parseInt() |
Parse a string and return an integer |
| JavaScript Loops |
| for |
The most common way to create a loop in JavaScript |
| while |
Set up conditions under which a loop executes |
| do while |
Similar to the while loop, however, it executes at least once and performs a check at the end to see if the condition is met to execute again |
| break |
Stop and exit the cycle if certain conditions are mets |
| continue |
Skip parts of the cycle if certain conditions are met |
| Escape Characters |
| \' |
Single quote |
| \" |
Double quote |
| \\ |
Backslash |
| \b |
Backspace |
| \f |
Form feed |
| \n |
New line |
| \r |
Carriage return |
| \t |
Horizontal tabulator |
| \v |
Vertical tabulator |
| JavaScript String Methods |
| charAt() |
Return a character at a specified position inside a string |
| charCodeAt() |
Give the unicode of character at that position |
| concat() |
Concatenate (join) two or more strings into one |
| fromCharCode() |
Return a string created from the specified sequence of UTF-16 code units |
| indexOf() |
Provide the position of the first occurrence of specified text within a string |
| lastIndexOf() |
Same as indexOf() but with the last occurrence, searching backwards |
| match() |
Retrieve the matches of a string against a search pattern |
| replace() |
Find and replace specified text in a string |
| search() |
Execute a search for a matching text and return its position |
| slice() |
Extract a section of a string and return it as a new string |
| split() |
Split a string object into an array of strings at a specified position |
| startsWith() |
Check whether a string begins with specified characters |
| substr() |
Similar to slice() but extracts a substring depended on a specified number of characters |
| substring() |
Similar to slice() but can’t accept negative indices |
| toLowerCase() |
Convert strings to lower case |
| toUpperCase() |
Convert strings to upper case |
| valueOf() |
Return the primitive value (that has no properties or methods) of a string object |
REGULAR EXPRESSION SYNTAX
Pattern Modifiers |
| e |
Evaluate replacement |
| i |
Perform case-insensitive matching |
| g |
Perform global matching |
| m |
Perform multiple line matching |
| s |
Treat strings as single line |
| x |
Allow comments and whitespace in pattern |
| U |
Ungreedy pattern |
| Brackets |
| [abc] |
Find any of the characters in the brackets |
| [^abc] |
Find any character not in the brackets |
| [0-9] |
Find digit specified in the brackets |
| [A-z] |
Find any character from uppercase A to lowercase z |
| (a|b|c) |
Find any of the alternatives separated with | |
| Metacharacters |
| . |
Find a single character, except newline or line terminator |
| \w |
Word character |
| \W |
Non-word character |
| \d |
A digit |
| \D |
A non-digit character |
| \s |
Whitespace character |
| \S |
Non-whitespace character |
| \b |
Find a match at the beginning/end of a word |
| \B |
Find a match not at the beginning/end of a word |
| \u0000 |
NUL character |
| \n |
A new line character |
| \f |
Form feed character |
| \r |
Carriage return character |
| \t |
Tab character |
| \v |
Vertical tab character |
| \xxx |
Character specified by an octal number xxx |
| \xdd |
Latin character specified by a hexadecimal number dd |
| \udddd |
Unicode character specified by a hexadecimal number dddd |
| Quantifiers |
| n+ |
Match any string that contains at least one n |
| n* |
Any string that contains zero or more occurrences of n |
| n? |
Any string that contains zero or one occurrences of n |
| n{X} |
Any string that contains a sequence of X n’s |
| n{X,Y} |
Strings that contains a sequence of X to Y n’s |
| n{X,} |
Matches any string that contains a sequence of at least X n’s |
| n$ |
Any string with n at the end of it |
| ^n |
String with n at the beginning of it |
| ?=n |
Any string that is followed by a specific string n |
| ?!n |
String that is not followed by a specific string n |
| Number Properties |
| MAX_VALUE |
Maximum numeric value representable in JavaScript |
| MIN_VALUE |
Smallest positive numeric value representable in JavaScript |
| NaN |
The “Not-a-Number” value |
| NEGATIVE_INFINITY |
Negative Infinity value |
| POSITIVE_INFINITY |
Positive Infinity value |
| Number Methods |
| toExponential() |
Return a string with a rounded number written as exponential notation |
| toFixed() |
Return string of a number with a specified number of decimals |
| toPrecision() |
Return string of a number written with a specified length |
| toString() |
Return a number as a string |
| valueOf() |
Return a number as a number |
| Math Properties |
| E |
Euler’s number |
| LN2 |
Natural logarithm of 2 |
| LN10 |
Natural logarithm of 10 |
| LOG2E |
Base 2 logarithm of E |
| LOG10E |
Base 10 logarithm of E |
| PI |
The number PI |
| SQRT1_2 |
Square root of 1/2 |
| SQRT2 |
Square root of 2 |
| Math Methods |
| abs(x) |
Return the absolute (positive) value of x |
| acos(x) |
Arccosine of x, in radians |
| asin(x) |
Arcsine of x, in radians |
| atan(x) |
Arctangent of x as a numeric value |
| atan2(y,x) |
Arctangent of the quotient of its arguments |
| ceil(x) |
Value of x rounded up to its nearest integer |
| cos(x) |
Cosine of x (x is in radians) |
| exp(x) |
Value of Ex |
| floor(x) |
Value of x rounded down to its nearest integer |
| log(x) |
Natural logarithm (base E) of x |
| max(x,y,z,...,n) |
Number with highest value |
| min(x,y,z,...,n) |
Number with lowest value |
| pow(x,y) |
X to the power of y |
| random() |
Random number between 0 and 1 |
| round(x) |
Value of x rounded to its nearest integer |
| sin(x) |
Sine of x (x is in radians) |
| sqrt(x) |
Square root of x |
| tan(x) |
Tangent of an angle |
| Dates |
| Date() |
Create a new date object with the current date and time |
| Date(2017, 5, 21, 3, 23, 10, 0) |
Create a custom date object. The numbers represent year, month, day, hour, minutes, seconds, milliseconds. You can omit anything you want except for year and month. |
| Date(“2017-06-23”) |
Date declaration as a string |
| getDate() |
Get the day of the month as a number (1-31) |
| getDay() |
Get the weekday as a number (0-6) |
| getFullYear() |
Get the year as a four digit number (yyyy) |
| getHours() |
Get the hour (0-23) |
| getMilliseconds() |
Get the millisecond (0-999) |
| getMinutes() |
Get the minute (0-59) |
| getMonth() |
Get the month as a number (0-11) |
| getSeconds() |
Get the second (0-59) |
| getTime() |
Get the time (milliseconds since January 1, 1970) |
| getUTCDate() |
Day (date) of the month in the specified date according to universal time (also available for day, month, fullyear, hours, minutes etc.) |
| parse |
Parse a string representation of a date, and return the number of milliseconds since January 1, 1970 |
| setDate() |
Set the day as a number (1-31) |
| setFullYear() |
Set the year (optionally month and day) |
| setHours() |
Set the hour (0-23) |
| setMilliseconds() |
Set the milliseconds (0-999) |
| setMinutes() |
Set the minutes (0-59) |
| setMonth() |
Set the month (0-11) |
| setSeconds() |
Set the seconds (0-59) |
| setTime() |
Set the time (milliseconds since January 1, 1970) |
| setUTCDate() |
Set the day of the month for a specified date according to universal time (also available for day, month, fullyear, hours, minutes etc.) |
DOM MODE
Node Properties |
| attributes |
Live collection of all attributes registered to an element |
| baseURI |
Absolute base URL of an HTML element |
| childNodes |
Collection of an element’s child nodes |
| firstChild |
First child node of an element |
| lastChild |
Last child node of an element |
| nextSibling |
Next node at the same node tree level |
| nodeName |
Name of a node |
| nodeType |
Type of a node |
| nodeValue |
Value of a node |
| ownerDocument |
Top-level document object for current node |
| parentNode |
Parent node of an element |
| previousSibling |
Node immediately preceding the current one |
| textContent |
Textual content of a node and its descendants |
| Node Methods |
| appendChild() |
Add a new child node to an element as the last child node |
| cloneNode() |
Clone HTML element |
| compareDocumentPosition() |
Compare the document position of two elements |
| getFeature() |
Return an object which implements the APIs of a specified feature |
| hasAttributes() |
Return true if an element has any attributes, else return false |
| hasChildNodes() |
Return true if an element has any child nodes, else return false |
| insertBefore() |
Insert a new child node before a specified, existing child node |
| isDefaultNamespace() |
Return true if a specified namespaceURI is the default, else return false |
| isEqualNode() |
Check if two elements are equal |
| isSameNode() |
Check if two elements are the same node |
| isSupported() |
Return true if a specified feature is supported on the element |
| lookupNamespaceURI() |
Return the namespaceURI associated with a given node |
| lookupPrefix() |
Return a DOMString containing the prefix for a given namespaceURI, if present |
| normalize() |
Join adjacent text nodes and remove empty text nodes in an element |
| removeChild() |
Remove a child node from an element |
| replaceChild() |
Replace a child node in an element |
| Element Methods |
| getAttribute() |
Return the specified attribute value of an element node |
| getAttributeNS() |
Return string value of the attribute with the specified namespace and name |
| getAttributeNode() |
Get the the specified attribute node |
| getAttributeNodeNS() |
Return the attribute node for the attribute with the given namespace and name |
| getElementsByTagName() |
Provide a collection of all child elements with the specified tag name |
| getElementsByTagNameNS() |
Return a live HTML collection of elements with a certain tag name belonging to the given namespace |
| hasAttribute() |
Return true if an element has any attributes, else return false |
| hasAttributeNS() |
Provide a true/false value indicating whether the current element in a given namespace has the specified attribute |
| removeAttribute() |
Remove a specified attribute from an element |
| removeAttributeNS() |
Remove the specified attribute from an element within a certain namespace |
| removeAttributeNode() |
Take away a specified attribute node and return the removed node |
| setAttribute() |
Set or change the specified attribute to a specified value |
| setAttributeNS() |
Add a new attribute or change the value of an attribute with the given namespace and name |
| setAttributeNode() |
Set or change the specified attribute node |
| setAttributeNodeNS() |
Add a new namespaced attribute node to an element |
| Browser Window Properties |
| closed |
Check whether a window has been closed or not and return true or false |
| defaultStatus |
Set or return the default text in the statusbar of a window |
| document |
Return the document object for the window |
| frames |
Return all iframe elements in the current window |
| history |
Provide the History object for the window |
| innerHeight |
Inner height of a window’s content area |
| innerWidth |
Inner width of the content area |
| length |
Return the number of iframe elements in the window |
| location |
Return the location object for the window |
| name |
Set or return the name of a window |
| navigator |
Return the Navigator object for the window |
| opener |
Return a reference to the window that created the window |
| outerHeight |
Outer height of a window, including toolbars/scrollbars |
| outerWidth |
Outer width of a window, including toolbars/scrollbars |
| pageXOffset |
Number of pixels by which the document has been scrolled horizontally |
| pageYOffset |
Number of pixels by which the document has been scrolled vertically |
| parent |
Parent window of the current window |
| screen |
Return the Screen object for the window |
| screenLeft |
Horizontal coordinate of the window (relative to screen) |
| screenTop |
Vertical coordinate of the window |
| screenX |
Same as screenLeft but needed for some browsers |
| screenY |
Same as screenTop but needed for some browsers |
| self |
Return the current window |
| status |
Set or return the text in the statusbar of a window |
| top |
Return the topmost browser window |
| Browser Window Methods |
| alert() |
Display an alert box with a message and an OK button |
| blur() |
Remove focus from the current window |
| clearInterval() |
Clear a timer set with setInterval() |
| clearTimeout() |
Clear a timer set with setTimeout() |
| close() |
Close the current window |
| confirm() |
Display a dialog box with a message and OK and Cancel buttons |
| focus() |
Set focus to the current window |
| moveBy() |
Move a window relative to its current position |
| moveTo() |
Move a window to a specified position |
| open() |
Open a new browser window |
| print() |
Print the content of the current window |
| prompt() |
Display a dialog box that prompts the visitor for input |
| resizeBy() |
Resize the window by the specified number of pixels |
| resizeTo() |
Resize the window to a specified width and height |
| scrollBy() |
Scroll the document by a specified number of pixels |
| scrollTo() |
Scroll the document to specified coordinates |
| setInterval() |
Call a function or evaluate an expression at specified intervals |
| setTimeout() |
Call a function or evaluate an expression after a specified interval |
| stop() |
Stop the window from loading |
| Screen Properties |
| availHeight |
Return the height of the screen (excluding the Windows Taskbar) |
| availWidth |
Return the width of the screen (excluding the Windows Taskbar) |
| colorDepth |
Return the bit depth of the color palette for displaying images |
| height |
The total height of the screen |
| pixelDepth |
The color resolution of the screen in bits per pixel |
| width |
The total width of the screen |
JAVASCRIPT EVENTS
JavaScript Mouse Events |
| onclick |
When user clicks on an element |
| oncontextmenu |
When user right-clicks on an element to open a context menu |
| ondblclick |
When user double-clicks on an element |
| onmousedown |
When user presses a mouse button over an element |
| onmouseenter |
When user moves pointer onto an element |
| onmouseleave |
When user moves pointer away from an element |
| onmousemove |
When user moves pointer while it is over an element |
| onmouseover |
When user moves pointer onto an element or one of its children |
| onmouseout |
When user moves pointer away from an element or one of its children |
| onmouseup |
When user releases a mouse button while over an element |
| JavaScript Keyboard Events |
| onkeydown |
When user is pressing a key down |
| onkeypress |
When user starts pressing a key |
| onkeyup |
When user releases a key |
| JavaScript Frame Events |
| onabort |
When loading of media is aborted |
| onbeforeunload |
Before the document is about to be unloaded |
| onerror |
When an error occurs while loading an external file |
| onhashchange |
When the anchor part of a URL has changed |
| onload |
When an object has loaded |
| onpagehide |
When user navigates away from a webpage |
| onpageshow |
When user navigates to a webpage |
| onresize |
When user resizes document view |
| onscroll |
When user is scrolling an element’s scrollbar |
| onunload |
When a page has unloaded |
| JavaScript Form Events |
| onblur |
When an element loses focus |
| onchange |
When the content of a form element changes (for input, select, and textarea) |
| onfocus |
When an element gets focus |
| onfocusin |
When an element is about to get focus |
| onfocusout |
When an element is about to lose focus |
| oninput |
User input on an element |
| oninvalid |
When an element is invalid |
| onreset |
When a form is reset |
| onsearch |
When a user types something in a search field (for input="search") |
| onselect |
When user selects some text (for input and textarea) |
| onsubmit |
When a form is submitted |
| JavaScript Drag Events |
| ondrag |
When user drags an element |
| ondragend |
When user has finished dragging the element |
| ondragenter |
When the dragged element enters a drop target |
| ondragleave |
When the dragged element leaves the drop target |
| ondragover |
When the dragged element is on top of the drop target |
| ondragstart |
When user starts to drag an element |
| ondrop |
Dragged element is dropped on the drop target |
| JavaScript Clipboard Events |
| oncopy |
When user copies content of an element |
| oncut |
When user cuts an element’s content |
| onpaste |
When user pastes content in an element |
| JavaScript Media Events |
| onabort |
When media loading is aborted |
| oncanplay |
When browser can start playing media (e.g. a file has buffered enough) |
| oncanplaythrough |
When browser can play through media without stopping |
| ondurationchange |
When duration of media changes |
| onended |
When media has reached its end |
| onerror |
When an error occurs while loading an external file |
| onloadeddata |
When media data is loaded |
| onloadedmetadata |
When metadata (like dimensions and duration) is loaded |
| onloadstart |
When browser starts looking for specified media |
| onpause |
When media is paused either by user or automatically |
| onplay |
When media has been started or is no longer paused |
| onplaying |
When media is playing after having been paused or stopped for buffering |
| onprogress |
When browser is in the process of downloading media |
| onratechange |
When playing speed of media changes |
| onseeked |
When user has finished moving/skipping to a new position in media |
| onseeking |
When user starts moving/skipping |
| onstalled |
When browser is trying to load unavailable media |
| onsuspend |
When browser is intentionally not loading media |
| ontimeupdate |
The playing position has changed (e.g. because of fast forward) |
| onvolumechange |
When media volume has changed (including mute) |
| onwaiting |
When media has paused but is expected to resume (for example, buffering) |
| Animation |
| animationend |
When CSS animation is complete |
| animationiteration |
When CSS animation is repeated |
| animationstart |
When CSS animation has started |
| Miscellaneous |
| transitionend |
When CSS transition is complete |
| onmessage |
When a message is received through the event source |
| onoffline |
When browser starts to work offline |
| ononline |
When browser starts to work online |
| onpopstate |
When the window’s history changes |
| onshow |
When a menu element is shown as a context menu |
| onstorage |
When a Web Storage area is updated |
| ontoggle |
When user opens or closes the details element |
| onwheel |
When mouse wheel rolls up or down over an element |
| ontouchcancel |
When screen touch is interrupted |
| ontouchend |
When user’s finger goes off touch screen |
| ontouchmove |
When user drags a finger across the screen |
