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.

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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.
deepMerge.js. Deep merge two or more objects or arrays.
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.
getFlagEmoji.js. Get the flag emoji for a two-letter country code.
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.