JavaScript HTML DOM Elements

Finding HTML Elements

To do so, you have to find the elements first. There are several ways to do this:

• Finding HTML elements by id
• Finding HTML elements by tag name
• Finding HTML elements by class name
• Finding HTML elements by CSS selectors
• Finding HTML elements by HTML object collections

Finding HTML Element by Id

var myElement = document.getElementById("intro");

Finding HTML Elements by Tag Name

var x = document.getElementsByTagName("p");

var x = document.getElementById("main");
var y = x.getElementsByTagName("p");

Finding HTML Elements by Class Name

var x = document.getElementsByClassName("intro");

Finding HTML Elements by CSS Selectors

var x = document.querySelectorAll("p.intro");

The querySelectorAll() method does not work in Internet Explorer 8 and earlier versions.

Finding HTML Elements by HTML Object Collections

var x = document.forms["frm1"];
var text = "";
var i;
for (i = 0; i < x.length; i++) {
  text += x.elements[i].value + "<br>";
}
document.getElementById("demo").innerHTML = text;