Helper Functions

Helper functions make complicated or repetitive tasks a bit easier, and keep your code DRY (an acronym for Don’t Repeat Yourself).

Unless otherwise noted, these helper functions work in all modern browsers on desktop and mobile. You can extend support back further with polyfills.

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The Functions

animate.js. Apply a CSS animation to an element.
arrayIntersect.js. Get the intersecting values between two arrays.
buildQuery.js. Build a query string from an object of data.
cleanHTML.js. Sanitize an HTML string to reduce the risk of XSS attacks.
createColor.js. Create a random color value.
decodeHTML.js. Decode HTML entities from an encoded string.
dedupe.js. Remove duplicate items from an array.
deepAssign.js. Deep merge two or more objects into the first.
emitEvent.js. Emit a custom event.
encodeHTML.js. Encode the HTML in a user-submitted string to reduce the risk of XSS attacks.
getContrast.js. Get the contrasting color for any hex color.
getCookie.js. Get the value of a cookie.
getMonths.js. Get a formatted list of months.
getParam.js. Get the value of a query string from a URL.
getParams.js. Get all URL parameters from a query string.
parseJWT.js. Decode the payload from a JSON Web Token (JWT).
randomNumber.js. Get a random integer with a minimum and maximum value.
randomString.js. Generate, hash, and encode cryptographically random strings.
range.js. Create a range of numbers between two values.
round.js. Round to the nearest whole number.
scrollDistance.js. Run a callback after the user scrolls, calculating the distance and direction scrolled.
serialize.js. Serialize all form data into an object. Fields must have a name property.
shuffle.js. Randomly shuffle an array.
trueTypeOf.js. More accurately check the type of a JavaScript object.