Essentials

Question 1

Get element collection

var elements = $(‘div’);

Answer 1

var elements = document.queryAll(‘div’);

Question 2

Get element collection in a specific container

var elements = $(‘div’, container);

Answer 2

var elements = container.queryAll(‘div’);

Question 3

Create new element

var element = $(‘div’);

Answer 3

var element = document.createElement(‘div’);

Question 4

Execute function when document is fully loaded –document.ready

$(function() {

console.log( “ready!” );

});

or

$( document ).ready(function() {

console.log( “ready!” );

});

Answer 4

document. addEventListener(‘DOMContentLoaded’, function() {
console. log( “ready!” );

});

Question 5

Each – Iterate over a jQuery object, executing a function for each matched element.

elements.each(function() {

$( this ).addClass( “foo” );

});

$( “li” ).each(function() {

$( this ).addClass( “foo” );

});

Answer 5

ES6

for (var element of elements) element.doSomething();

ES5

elements.forEach(function(element) { element.doSomething();

});

For large collections use

for (var id = 0; id < elements.length; id++) elements[id].doSomething();