Reference Guide
A quick reference for commonly used JavaScript methods and browser APIs.
Unless otherwise noted, these work in all modern browsers, and IE9+. You can extend support back further with polyfills.
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Selectors
Loops
Classes
Styles
Attributes
Event Listeners
Strings
Numbers
- parseInt() - Convert a string into an integer (whole number).
- parseFloat() - Convert a string into a point number (a number with decimal points).
- Number() - Convert a string into a number.
- Number.toFixed() - Format a number to a fixed number of decimal places.
- Number.toString() - Convert a number to a string.
- Basic math - Do basic arithmetic with JavaScript.
- Comparisons - Compare two numbers.
- Math.abs() - Get the absolute value of a number.
- Math.floor() - Get the largest integer less than or equal to a number.
- Math.ceil() - Get the smallest integer greater than or equal to a number.
- Math.max() - Get the largest number from a set of numbers
- Math.min() - Get the lowest number from a set of numbers.
- Math.random() - Return a random float between
0
and 1
.
Arrays
Objects
HTML and Text
DOM Injection
Traversing the DOM
The Viewport
Distances
Browser Storage
- Cookies - Set cookie values.
- localStorage - Store data locally in the browser for later use.
- sessionStorage - Store data locally for the duration of the current browser session.
JSON
Ajax and APIs
JavaScript-Free Components