Cheat sheet: Flash Player HTTP talking with HTTPService, URLLoader and friends

	HTTPService	URLLoader	Loader	FileReference	MultipartURLLoader
	mx.rpc.http.HTTPService mx.rpc.http.mxml.HTTPService	flash.net.URLLoader	flash.display.Loader	flash.net.FileReference	ru.inspirit.net.MultipartURLLoader
Sending format
	httpService.contentType=	URLRequest.data=	-	-	-
Text	(variables)	string	-	-	x
XML	HTTPService.CONTENT_TYPE_XML	-	-	-	x
Binary	-	data as ByteArray	-	fileReference.load() to load a local file	x
Image	-	1)	-	fileReference.load() to load a local image	1)
HTML form	-	-	-	- (FileReference sends files in HTML form)	x
URL-encoded variables	HTTPService.CONTENT_TYPE_FORM	URLVariables	-	-	x
HTTP headers
Send		only for POST requests: urlRequest.requestHeaders=[new URLRequestHeader()] 3)	only for POST requests: urlRequest.requestHeaders=[new URLRequestHeader()] 3)	only for POST request: urlRequest.requestHeaders=[new URLRequestHeader()] 3)	addHttpHeader() 3)
Receive 4)	-	-	-	-	-
HTTP Method
	httpService.method=	urlRequest.method=	urlRequest.method=	urlRequest.method=
GET	HTTPRequestMessage.GET_METHOD	URLRequestMethod.GET	URLRequestMethod.GET	URLRequestMethod.GET	-
POST	HTTPRequestMessage.POST_METHOD	URLRequestMethod.POST	URLRequestMethod.POST	URLRequestMethod.POST	x
PUT	-	-	-	-	-
DELETE	-	-	-	-	-
Other
Tokens	AsyncToken	-	-	-	-
Follows HTTP Redirects	?
HTTP status	-	-	-	-	-
Events
	FaultEvent ResultEvent	HTTPStatusEvent.HTTP_STATUS but property "status" is empty, Event.COMPLETE IOErrorEvent SecurityErrorEvent	only loader.contentLoaderInfo dispatches events: HTTPStatusEvent but property "status" is empty Event.COMPLETE IOErrorEvent No SecurityErrorEvent	HTTPStatusEvent.HTTP_STATUS but property "status" is empty, Event.COMPLETE DataEvent.UPLOAD_COMPLETE_DATA only dispatch when data arrives from server. IOErrorEvent SecurityErrorEvent
Errors
	httpService.send(parameters) For POST request, parameters must be non null. Otherwise, the method is changed to GET.	try {     urlLoader.load(urlRequest) } catch(e:SecurityError){} } catch(e:ArgumentError){} } catch(e:TypeError){} } catch(e:MemoryError){}	try {     loader.load(urlRequest, loaderContext) catch (e:IOError) {} catch (e:SecurityError) {}  - If uploading a file, it must be initiated by user event. - Don't reuse the instance of loader.	try {     fileReference.upload(urlRequest) } catch(e:SecurityError){} } catch(e:ArgumentError){} } catch(e:IllegalOperationError){} } catch(e:MemoryError){}
Receiving format
	httpService.resultFormat =	urlLoader.dataFormat=
Text	HTTPService.RESULT_FORMAT_TEXT	URLLoaderDataFormat.TEXT	-
XML	HTTPService.RESULT_FORMAT_E4X	-	-
Binary	-	URLLoaderDataFormat.BINARY	-
Image (jpg, png, gif)	-	2)	x	2)
swf files	-	-	x
URL variables	HTTPService.RESULT_FORMAT_OBJECT	URLLoaderDataFormat.VARIABLES
Received data
		var resultXML:XML = urlLoader.data as XML		try {     fileReference.save(data, defaultFileName) } catch(e:IllegalOperationError){} } catch(e:ArgumentError){} } catch(e:Error){} } catch(e:MemoryError){}

1) Bitmaps created in Flash Player can be encoded with e.g. PNGEncoder from corelib and sent with these classes.
2) The image can be loaded as binary, converted by e.g. JPGEncoder and displayed.
3) Depending on the Flash Player version, different HTTP headers are blocked. See Adobe KB for complete list and an article about the authorization header.
4) Flash Player cannot receive HTTP headers.

General remarks

• User interaction: Don't forget that some interactions require an event triggered directly by the user. For example, fileReference.save() must be called by e.g. a mouseClickHandler.
• GC: make sure, the caller object does not get garbage collected, like local variables are.
• URL length: The maximum length of an URL is not specified. In practice, Internet Explorer seems to have the lowest barrier with 2048 characters.
• URLStream: I have never used URLStream so far, so it's not yet in the table.
• Security: Read the Flash Player 10 security white paper.
• Incomplete: This table gives an overview over the most relevant use cases. The links to the API documentation reveal all the beauty...

//TODO

• Firefox HTTPS FileReference upload issue, http://bugs.adobe.com/jira/browse/FP-201
• HTTPService GET doesn't support request headers, https://bugs.adobe.com/jira/browse/SDK-12505
• 'GET' request through URLRequest ignores 'Content-Type' request header?, http://bugs.adobe.com/jira/browse/FP-1273
• Request headers don't work on GET with URLLoader, http://bugs.adobe.com/jira/browse/FP-209