Sending objects between flash movies with POST

From Birnam Designs Wiki

It is possible to send entire objects between Flex and Flash movies via POST using ByteArray and Base64Encoder/Base64Decoder.

Note: The Base64Encoder/Base64Decoder classes are in the mx.utils package. If you are making a non-Flex interface, there are third party Base64 classes available.

The key to restoring the information as a class instead of a simple Object is the registerClassAlias and getQualifiedClassName functions. These allow the class information to be retained. Otherwise, the readObject function will successfully output variables in a simple object, but if you tried to cast this to a class type, it will result in a null variable.

Data Class

As far as I can tell, this can be any type of class. The entire state is stored.

package {
	public class DataClass {
		public var a:Number;
		public var b:String;
		public var c:Boolean;
 
		public function DataClass() {
		}
	}
}

Sender Class

package {
	import mx.utils.Base64Encoder;
	import flash.utils.getQualifiedClassName;
	import flash.net.registerClassAlias;
	import flash.net.URLRequest;
	import flash.net.URLRequestMethod;
	import flash.net.URLVariables;
 
	public class Sender {
 
		public function Sender() {
			// create DataClass object to use,
			// and register its class using its
			// qualified class name
			var dc:DataClass = new DataClass();
			// necessary so flash will know how to encode as a class
			registerClassAlias(getQualifiedClassName(cbdata), MHouseData);
 
			// create a ByteArray from the object
			var ba:ByteArray = new ByteArray();
			ba.writeObject(cbdata);
 
			// create a Base64 string from the ByteArray
			var b64:Base64Encoder = new Base64Encoder();
			b64.encodeBytes(ba);
			var b64string:String = b64.toString();
 
			// sent it to the receiving page
			var u:URLRequest = new URLRequest("nextswf.php");
			var v:URLVariables = new URLVariables();
			v.dcdata = b64string;
			u.data = v;
 
			// since it's a string, you can (with only some limitations)
			// use GET instead, but it does look like a big
			// junk string on the end of the url!
			u.method = URLRequestMethod.POST;
			navigateToURL(u, "_self");
		}
	}
}

Receiving Class

package {
	import mx.utils.Base64Decoder;
	import flash.utils.getQualifiedClassName;
	import flash.net.registerClassAlias;
 
	public class Receiver {
		// this assumes you have used PHP or other
		// to add the Base64 string to FlashVars.
		// -- don't forget, it will probably be necessary to
		//    urlencode or equivalent to make sure the
		//    Base64 string is passed correctly to flash
		var dcdata:String = Application.application.parameters.dcdata;
 
		// must create an instance to retreive the classname
	    var dc:DataClass = new MHouseData();
		// necessary so flash will know how to decode as a class
	    registerClassAlias(getQualifiedClassName(cbdata), MHouseData);
 
		// decode the Base64 string
	    var b64:Base64Decoder = new Base64Decoder();
	    b64.decode(dcdata);
 
		// save back out to ByteArray
	    var ba:ByteArray = b64.toByteArray();
 
		// export as an object
	    var obj:Object = ba.readObject();
 
		// ensure that it is casted as the DataClass
	    dc = obj as DataClass;
 
	}
}

From Birnam Designs Wiki

Data Class

Sender Class

Receiving Class

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