Comments on: Update 2: Faking Enums in AS3

By: Scott

Scott — Thu, 24 Dec 2009 22:07:43 +0000

Ok new post up with more fun toys for the enum class. This should get it pretty much par with .NET’s enums (minus ‘flag’ ability…maybe will get to that later).

http://scottbilas.com/2009/12/24/ultimate-as3-fake-enums/

By: Mikko Korpela

Mikko Korpela — Thu, 24 Dec 2009 20:27:39 +0000

On a second thought you could use an enum helper class that is constructed in a static method in the subclass:

public static function helper():Helper { return super.getHelperFor(ThisClass.class); }

Helper could have methods for value iteration and enum from string getting etc. For performance reasons all helpers could be cached in a static dictionary in EEnum class.

By: Mikko Korpela

Mikko Korpela — Thu, 24 Dec 2009 19:47:22 +0000

If you could do that with static functions in the super class that would be a great xmas gift.. I think that the only way is to write a static method in the subclass that calls a superclass method with the subclass as a parameter ( like in the enum init)

By: ken ehrman

ken ehrman — Thu, 24 Dec 2009 16:33:43 +0000

quick additions you my be interested in.

/** public function parseString(value:String):*
* Takes a string value and attempts to find
* a matching constant in the class returns a reference to that constant
* Throws an error if none found.
*/
public function parseString(stringValue:String):* {

// grabs all information about the class
var classObj = getDefinitionByName(getQualifiedClassName(this));
var type :XML = flash.utils.describeType(classObj);

// loops through the constant collecion
for each (var constant :XML in type.constant) {
if (stringValue == constant.@name) {
// found. return reference to constant.
return classObj[constant.@name];
}
}
// if no match found
throw new Error(value + ” is invalid string value.”);
}

/** public function parseStringCaseInsenstive(value:String):*
* Takes a string value and attempts to find
* a matching constant in the class returns a reference to that constant
* Throws an error if none found.
*/
public function parseStringCaseInsenstive(stringValue:String):* {

// grabs all information about the class
var classObj = getDefinitionByName(getQualifiedClassName(this));
var type :XML = flash.utils.describeType(classObj);

// loops through the constant collecion
for each (var constant :XML in type.constant) {
// test case-insensitive
if (stringValue.toUpperCase() == constant.@name.toUpperCase()) {
// found. return reference to constant.
return classObj[constant.@name];
}
}
// if no match found
throw new Error(value + ” is invalid string value.”);
}

By: Scott

Scott — Thu, 24 Dec 2009 03:52:08 +0000

I’m working on a post which addresses the iteration problem. Stay tuned.

By: Miko Korpela

Miko Korpela — Thu, 15 Oct 2009 06:43:39 +0000

Hello!

Thank you for this super cool class!

I was just wondering if someone has figured out a simple way to add an enum iterator?

I tried to add a static _values array to the EEnum class but it will contain all EEnum subclasses.

I tried to add a static dictionary with enum class name as a key but then I would have to find out the name of the caller class but there seems to be no way to get the stack trace in flex.

By: Jason McIntosh

Jason McIntosh — Thu, 20 Aug 2009 15:30:59 +0000

You can’t do that in AS3, alas.

By: Scott

Scott — Tue, 23 Jun 2009 20:53:50 +0000

I didn’t know you could do that in Actionscript. If you can, then that is definitely a better way. Safer, as you said. Thanks!

By: larnima

larnima — Tue, 23 Jun 2009 10:09:19 +0000

Hello,

I’m a beginner in AS3 but I was thinking of use this signature for the ctor :
protected static function initEnum(i_type :* extends Enum) :void

just like I do in Java-like language.

Could we do something like this in AS3 ?
because that could add safety to the Enum-Fake : no one could ask the init on something that did not extends EEnum, did it ?

(N.B. : I apologize for my poor English … )