ActionScript: Using 'in' on protected/private variables?
Is there any way to mimic the in
operator, but testing for the existence of protected
or private
fields?
For example, this:
<mx:Script>&开发者_StackOverflow中文版lt;![CDATA[
public var pub:Boolean = true;
protected var prot:Boolean = true;
private var priv:Boolean = true;
]]></mx:Script>
<mx:creationComplete><![CDATA[
for each (var prop in ["pub", "prot", "priv", "bad"])
trace(prop + ":", prop in this);
]]></mx:creationComplete>
Will trace:
pub: true prot: false priv: false bad: false
When I want to see:
pub: true prot: true priv: true bad: false
you can just try to access it and catch resulting errors. :)
in
is unaware of any namespaces currently opened (including private and protected in your case), and will only look within the public namespace.
in
for objects actually just calls Object::hasOwnProperty
. Unfortunately, you effectively cannot override this method to alter its behaviour. the only class that can influence it is flash.utils::Proxy
, which actually uses flash_proxy::hasProperty
to to determine the return value of hasOwnproperty
.
So no, other than trying, there's no other way sadly.
How about:
<mx:creationComplete>
for each (var prop:String in ["pub", "prot", "priv", "bad"])
{
try
{
t.text += prop + ":" + this[prop] + "\n";
}
catch (e:Error)
{
t.text += prop + ": false" + "\n";
}
}
</mx:creationComplete>
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