cancel (FileReference.cancel メソッド)

import flash.net.FileReference;

var listener:Object = new Object();

listener.onProgress = function(file:FileReference, bytesLoaded:Number, bytesTotal:Number):Void {
    trace("onProgress with bytesLoaded: " + bytesLoaded + " bytesTotal: " + bytesTotal);
    if(bytesLoaded >= (bytesTotal / 2)) {
        file.cancel();
    }
}

var fileRef:FileReference = new FileReference();
fileRef.addListener(listener);
var url:String = "http://www.adobe.com/platform/whitepapers/platform_overview.pdf";
fileRef.download(url, "FlashPlatform.pdf");