Convert Flash 5 to AS 2.0, and a new JSFL Command

I’m doing a project where I need to convert a ton of code from Flash 5 to Flash MX 2004, AS 2.0. The code needs to retain as much of the original structure as possible. (It’s for a very popular Flash 5 book that is being re-released). After a lot of messing around, I finally came up with a guideline for myself that at least codifies the process. I thought this might be useful to others who have to do anything similar.

1. Move all code to the main timeline.
   • Take any clipEvent code and turn it into functions on _root.
   • Assign the functions as event handlers on the associated clips.
   • Re-scope the event handlers as necessary. There were changes in the scope chain from Flash 5 to MX. Generally this means sticking “this” in front of every variable in your handlers.
   • Remove any “controller clips” and the like”.
2. Handle any case issues. In AS1, myVar == myvar. Not in AS2. I created a JSFL file that helps with this. Read on…
3. Initialize variables. In AS1/Flash5, if x is undefined, x++ equals 1. In AS2/2004, it equals NaN. A good trick to find a lot of these is searching for +=, -=, ++, –. Make sure whatever is being incremented has been set to something, usually 0, beforehand.
4. Change your publish profile to Flash 7 Player, AS2.0. At this point, the code should work. But in reality, you’ll probably need to do some more debugging here. Get everything working before moving on.
5. Rethink any duplicateMovieClip code, try to turn it into attachMovieClip.
6. Type all variables, function parameters and returns:
   • myVar = 1; becomes var myVar:Number = 1;
   • function myFunc(param){} becomes function myFunc(param:String):Void {}
7. Upgrade deprecated actions. i.e. random() becomes Math.random(), etc. How far you want to go in this is up to you. I also do things like changing hardcoded stage size variables to Stage.width, Stage.height.
8. At this point, you should pretty much have a valid AS2.0 program. Depending on how complex it is, you might want to move into an OOP design with it. For example, if you are attaching a lot of movie clips and assigning a lot of properties and event handlers or other methods to it, or you are using prototype, it may make more sense to create a new class that extends MovieClip.

A lot of these are common sense, but it helped me to lay it out as a process.

As for Number 2, I created this JSFL Command that helps in the process. Put it in the Commands folder in your Flash Configuration folder. It’s a quick and dirty command. It just looks at the ActionScript on Frame 1 of the main time line. It makes a list of all alphabetical string segments and pares it down to those that are potential case-sensitivity offenders, and traces out that list. It’s up to you to do the search and replace. Not perfect, but it saved me a lot of time.