IO for Flash version?

Specifically, I’m using File.Exists(), StreamReader and StreamWriter, all of which are unsupported in Unity Flash version. I failed to find their counterparts on my own. Please, help me out.

Edit: Are there any Unity/C# substitutes? Native Flash API should work but I’d rather stay with C# if possible.

Edit2: When using import flash.filesystem.File; I get: Error: Definition flash.filesystem:File could not be found. Quick google search says it’s for AIR applications only - does that mean I can’t use it here? So what (class) can I?

I’ve never worked with Flash in Unity, but according to that page, you can use ActionScript API. So I guess you should look for a way to do that here.

Edit : I found that topic that may be helpful to you.