ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
HTTP communications
When your application runs in a browser, you can only use web services in the same Internet domain as the calling
SWF unless the server hosting the web service also hosts a cross-domain policy file that permits access from other
domains. A technique that is often used when a cross-domain policy file is not available is to proxy the requests
through your own server. Adobe Blaze DS and Adobe LiveCycle support web service proxying.
In AIR applications, a cross-domain policy file is not required when the web service call originates from the application
security sandbox. AIR application content is never served from a remote domain, so it cannot participate in the types
of attacks that cross-domain policies prevent. In HTML-based AIR applications, content in the application security
sandbox can make cross-domain XMLHttpRequests. You can allow content in other security sandboxes to make crossdomain
XMLHttpRequests as long as that content is loaded into an iframe.
More Help topics
“Website controls (policy files)” on page 1040
Adobe BlazeDS
Adobe LiveCycle ES2
REST architecture
XML-RPC
SOAP protocol
REST-style web service requests
Flash Player 9 and later, Adobe AIR 1.0 and later
REST-style web services use HTTP method verbs to designate the basic action and URL variables to specify the action
details. For example, a request to get data for an item could use the GET verb and URL variables to specify a method
name and item ID. The resulting URL string might look like:
http://service.example.com/?method=getItem&id=d3452
To access a REST-style web service with ActionScript, you can use the URLRequest, URLVariables, and URLLoader
classes. In JavaScript code within an AIR application, you can also use an XMLHttpRequest.
Programming a REST-style web service call in ActionScript, typically involves the following steps:
1 Create a URLRequest object.
2 Set the service URL and HTTP method verb on the request object.
3 Create a URLVariables object.
4 Set the service call parameters as dynamic properties of the variables object.
5 Assign the variables object to the data property of the request object.
6 Send the call to the service with a URLLoader object.
7 Handle the complete event dispatched by the URLLoader that indicates that the service call is complete. It is also
wise to listen for the various error events that can be dispatched by a URLLoader object.
For example, consider a web service that exposes a test method that echoes the call parameters back to the requestor.
The following ActionScript code could be used to call the service:
Last updated 6/6/2012
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