javascript functions cheat sheet code example

Example 1: javascript cheat sheet

Best Cheat Sheet:
https://websitesetup.org/wp-content/uploads/2020/09/Javascript-Cheat-Sheet.pdf

Example 2: javascript cheat sheet

/* Convenient interactive cheat sheet */ 'https://htmlcheatsheet.com/js/'
/* PDF VERSION */'https://websitesetup.org/wp-content/uploads/2020/09/Javascript-Cheat-Sheet.pdf'

Example 3: dom javascript cheat sheet

// Returns a reference to the element by its ID.
document.getElementById('someid');

// Returns an array-like object of all child elements which have all of the given class names.
document.getElementsByClassName('someclass');

// Returns an HTMLCollection of elements with the given tag name.
document.getElementsByTagName('LI');

// Returns the first element within the document that matches the specified group of selectors.
document.querySelector('.someclass');

// Returns a list of the elements within the document (using depth-first pre-order traversal of the document's nodes)
// that match the specified group of selectors.
document.querySelectorAll('div.note, div.alert');

Example 4: dom javascript cheat sheet

// create new elments
var newHeading = document.createElement('h1');
var newParagraph = document.createElement('p');

// create text nodes for new elements
var h1Text= document.createTextNode('This is a nice header text!');
var pText= document.createTextNode('This is a nice paragraph text!');

// attach new text nodes to new elements
newHeading.appendChild(h1Text);
newParagraph.appendChild(pText);

// elements are now created and ready to be added to the DOM.

Example 5: dom javascript cheat sheet

// grab element on page you want to add stuff to
var firstHeading = document.getElementById('firstHeading');

// add both new elements to the page as children to the element we stored in firstHeading.
firstHeading.appendChild(newHeading);
firstHeading.appendChild(newParagraph);

// can also insert before like so

// get parent node of firstHeading
var parent = firstHeading.parentNode;

// insert newHeading before FirstHeading
parent.insertBefore(newHeading, firstHeading);

Example 6: java script basik cheat sheeet

var pi = 3.141;
pi.toFixed(0);          // returns 3
pi.toFixed(2);          // returns 3.14 - for working with money
pi.toPrecision(2)       // returns 3.1
pi.valueOf();           // returns number
Number(true);           // converts to number
Number(new Date())      // number of milliseconds since 1970
parseInt("3 months");   // returns the first number: 3
parseFloat("3.5 days"); // returns 3.5
Number.MAX_VALUE        // largest possible JS number
Number.MIN_VALUE        // smallest possible JS number
Number.NEGATIVE_INFINITY// -Infinity
Number.POSITIVE_INFINITY// Infinity