vanilla javascript to jquery counterparts.

hi.js

// SELECT THE ELEMENT HAVING THE ID 'hello'
// vanilla
var element = document.getElementById('#hello');
// jquery:
var element = $("#hello");

// ---

// SELECT ALL body ELEMENTS
// vanilla
var element = document.getElementsByTagName('body');
// jquery:
var element = $("body");

// ---

// SELECT ALL ELEMENTS HAVING THE CLASS NAME 'items'
// vanilla
var element = document.getElementsByClassName('.items');

// jquery:
var element = $(".items");

// ---

// SET THE INNER HTML OF THE ELEMENT WHOSE ID IS hello
// vanilla
var element = document.getElementById('#hello');
element.innerHTML = "Hello World";
// jquery:
var element = $("#hello");
element.html("Hello World");

// ---

// SET THE FIRST INPUT ELEMENT'S VALUE
// vanilla
var element = document.getElementByTagName('input');
element[0].value = "Hello";
// jquery:
var element = $("input").first();
element.val("Hello World");


// ADD the class 'active' TO THE ELEMENT WHOSE ID is 'hello'
// vanilla
var element = document.getElementById('#hello');
element.className = 'active';
// jquery
var element = $("#hello");
element.addClass('active');