AS3 count the number of flashVars before entering if statement - actionscript-3

Question

I am creating a simple image viewer using AS3 and getting image URLs from flashVars in the HTML. I want to use an if
argument to have it perform one function if there is only one flashVar and another if there are more.
I have it reading the flashVars fine and can write if statments all day long, the trouble I am having is counting the number
of flashVars being passed from the HTML. here is a real dumbed down version of what I am trying to do (which doesnt work
because I can not figure out the correct process to follow):
var numberOfVars:Number = 0; // to store the number of flashVars
var paramObj:Object = LoaderInfo(this.root.loaderInfo).parameters; //get the flashVars
for each (paramObj in LoaderInfo(this.root.loaderInfo).parameters){
numberOfVars + 1;
}
var tf:TextField = new TextField();
addChild(tf);
tf.text = numberOfVars.toString(); // this returns '0' when runningn this code
if (numberOfVars < 2){
//do this
}
else {
//do this
}
thanks for your help guys.
Chris

Answer 1

You would want to increment numberOfVars
Looks like you have this:
numberOfVars + 1;
When you should have this:
numberOfVars++;
which is just short way of writing this:
numberOfVars = numberOfVars + 1;
or this:
numberOfVars += 1;

Answer 2

Just use a for(key in object) loop to track the amount of vars stored on root.loaderInfo.parameters.
var fvars:Object = root.loaderInfo.parameters;
var n:int = 0;
for(var i:String in fvars) n ++;
// n holds the amount of flashvars
if(n <= 1)
{
// one or no variables found
}
else
{
// more than one found
}
Also, you've done one of your operators wrong:
for each(paramObj in LoaderInfo(this.root.loaderInfo).parameters)
{
numberOfVars + 1; // <<<<<< here
}
You're looking for one of the following:
numberOfVars ++;
numberOfVars += 1;
numberOfVars = numberOfVars + 1;

Answer 3

I will offer a slightly different take on the conditional logic here. Instead of reacting to variables based on how many there are (introducing plenty of opportunity for unpredictable results) - why not base your conditional statements on what the vars actually are. This is my standard flashVar process:
var _loadParams:Object
private function init():void
{
_loadParams = new Object();
_loadParams = LoaderInfo(stage.loaderInfo).parameters;
someVar = String( parseParam( "someVar", "default value") );
}
private function parseParam(name:String, defaultValue:String):String
{
if (_loadParams.hasOwnProperty(name) && _loadParams[name] != "" && _loadParams[name] != "undefined")
{
return _loadParams[name];
}
else
{
return defaultValue;
}
}
This, obviously, is just testing for the presence of a value, but it could be easily altered to call some functionality based on those results:
if (_loadParams.hasOwnProperty(name) && _loadParams[name] != "" && _loadParams[name] != "undefined")
{
switch (name){
case 'param1':
doSomthing(name);
break;
case 'param2':
doSomthingElse(name);
break;
}
}
I don't know what you are trying to achieve, and this may be way off. But I thought I'd chime in ;)
Cheers!