DOM Scripting Web Design with JavaScript and the Document Object Model

 The HTML DOM is a standard for how to get, change, add, or delete HTML elements.

Nodes

　　Element nodes

　　Text nodes :  <p>text node is contained within element nodes</p>

　　Attribute nodes

Getting Elements:

　　getElementById

　　getElementsByTagName

　　getElementsByClassName

Getting and Setting Attributes:

　　getAttribute

　　setAttribute

What can libraries help you do:

　　Syntax

　　Selecting elements

　　Manipulating DOM document

　　Handling events

　　Animation

　　Ajax

CDN: Content delivery networks. If a number of sites use the same library, it would make sense to host that library in a common location that all the sites could access to.

 

childNodes:

function countBodyChildren() {
    var body_element = document.getElementsByTagName*"body")[0]
    alert()body_element.childNodes.length);
}
window.onload = countBodyChildren

node.firstChild == node.childNodes[0]

node.lastChild == node.childNodes[node.childNodes.length - 1]

 

nodeType:

　　Element nodes have a node Type value of 1

　　Attribute nodes have a node Type value of 2

　　Text Nodes have a node Type  value of 3

nodeValue

 

Graceful degradation:

still makes the web working for those without javascript enabled