ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
HTTP communications
The httpResponseStatus event (AIR)
In Adobe AIR, the URLStream class dispatches an httpResponseStatus event in addition to the httpStatus event.
The httpResponseStatus event is delivered before any response data. The httpResponseStatus event (represented
by the HTTPStatusEvent class) includes a responseURL property, which is the URL that the response was returned
from, and a responseHeaders property, which is an array of URLRequestHeader objects representing the response
headers that the response returned.
Loading data from external documents
Flash Player 9 and later, Adobe AIR 1.0 and later
When you build dynamic applications, it can be useful to load data from external files or from server-side scripts. This
lets you build dynamic applications without having to edit or recompile your application. For example, if you build a
“tip of the day” application, you can write a server-side script that retrieves a random tip from a database and saves it
to a text file once a day. Then your application can load the contents of a static text file instead of querying the database
each time.
The following snippet creates a URLRequest and URLLoader object, which loads the contents of an external text file,
params.txt:
var request:URLRequest = new URLRequest("params.txt");
var loader:URLLoader = new URLLoader();
loader.load(request);
By default, if you do not define a request method, Flash Player and Adobe AIR load the content using the HTTP GET
method. To send the request using the POST method, set the request.method property to POST using the static
constant URLRequestMethod.POST, as the following code shows:
var request:URLRequest = new URLRequest("sendfeedback.cfm");
request.method = URLRequestMethod.POST;
The external document, params.txt, that is loaded at run time contains the following data:
monthNames=January,February,March,April,May,June,July,August,September,October,November,Dece
mber&dayNames=Sunday,Monday,Tuesday,Wednesday,Thursday,Friday,Saturday
The file contains two parameters, monthNames and dayNames. Each parameter contains a comma-separated list that
is parsed as strings. You can split this list into an array using the String.split() method.
Avoid using reserved words or language constructs as variable names in external data files, because doing so makes
reading and debugging your code more difficult.
Once the data has loaded, the complete event is dispatched, and the contents of the external document are available
to use in the URLLoader’s data property, as the following code shows:
function completeHandler(event)
{
var loader2 = event.target;
air.trace(loader2.data);
}
If the remote document contains name-value pairs, you can parse the data using the URLVariables class by passing in
the contents of the loaded file, as follows:
Last updated 6/6/2012
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