XML (Extensible Markup Language) is a special format for structuring and storing data.
It is similar to HTML in that it uses tags to mark up content. XML tags are used to organize data in a predictable hierarchy. But XML tags (also called elements) are not predefined. You must define your own tags.
<?xml version="1.0"?> <base> <tag attribute="value"> <tag_in attribute="value">Data stored</tag_in> </tag> </base>- If you don't know what the XML documents are, study the tutorial from the page XML Documents.
The name E4X is a nickname used in ActionScript for XML in the ECMAScript standard. It's the same XML access standard that's used in JavaScript 2.0.
To create XML data in ActionScript code via E4X, we have two general options:
1. Write our XML data in literal form, just like a string, in a XML instance.
2. Create a new XML instance, and then add each element programmatically, by using the dot (.) operator, or with XML, XMLList methods.
• As a general rule, the XML structure must be added in an instance of the XML class.
- An XML object represents a portion of simple XML data such as an element, text node, attribute, comments.
- An XMLList is a numbered set, very much like an array, of XML objects..
// The XML instance with the complete XML data var pics:XML = <imglist> <image id="1"> <url>dir/img1.jpg</url> <title>Title img1</title> </image> </imglist>; trace(pics); // Displays in Output the XML structure- This code creates a XML data structure, in the "pics" variable, which stores the adress and title of an image. "trace(pics)" displays in Output this structure.
// Variables with data that must be added in XML var img_id:int = 1; var img_url:String = 'dir/img1.jpg'; var img_title:String = 'Title img1'; // XML instance with complete XML data var pics:XML = <imglist> <image id={img_id}> <url>{img_url}</url> <title>{img_title}</title> </image> </imglist>; trace(pics); // Displays in Output the XML structure
// The XML instance with the root tag var pics:XML = <imglist/>; // you can also use: XML(<imglist/>); pics.image.@id = 1; // Creates the tag <image>, includes an "id" attribute with the value of 1 pics.image.url = 'dir/img1.jpg'; // Add in the <image> element a tag <url> pics.image.title = 'Title img1'; // Add in the <image> element a tag <title> trace(pics);- This code creates and returns in Output the same XML structure as the one from the first example.
// XML instance with the root tag var pics:XML = <imglist/>; // Add each element // First the tag <image>, then within it: <url> and <title> pics.appendChild(<image id="1"></image>); pics.image.prependChild(<url>dir/img1.jpg</url>); pics.image.insertChildAfter(pics.image.url, <title>Title img1</title>); trace(pics);To download the FLA file with the examples in this lesson, click: Creating XML data with E4X.
<object type="application/x-shockwave-flash" data="file.swf" width="500" height="250"> <param name="src" value="file.swf" /> Your browser not support SWF. </object>
input:focus { background-color: #88fe88; }
var jsnstr = '{"url": "http://coursesweb.net/", "title": "Web Development Courses"}'; var obj = JSON.parse(jsnstr); alert(obj.url);
if (file_put_contents("file.txt", "content")) echo "The file was created"; else echo "The file can not be created";