JavaScript Basics: Difference between revisions
Jump to navigation
Jump to search
Line 38: | Line 38: | ||
== Prototypes == | == Prototypes == | ||
Every object has a <code>prototype</code> property. | |||
<pre> | <pre> | ||
Counter.prototype = { | Counter.prototype = { |
Revision as of 17:01, 18 April 2015
Link to external Javscript file
<head>
<title>Test</title>
<meta http-equiv="content-type" content="text/html;charset=utf-8" />
<script src="spectra.js" type="text/javascript" ></script>
</head>
Types
The built-in types are string
, number
, boolean
, null
, undefined
, object
.
Use typeof some_var
to get the type.
The following are considered false: false
, 0
, ""
, null
, undefined
, NaN
.
Arrays
Arrays are special objects.
var my_array = []; // make a new array
Strings
" Hello ".trim() // "Hello"
Objects
var new_object = {}; // make a new empty object new_object.name = "Bill"; // create a property new_object["name"] = "Bill"; // same thing for (var key in my_object){ // iterate over an object // do something with key // value is my_object[key] }
Prototypes
Every object has a prototype
property.
Counter.prototype = { };