class Foo {
public function bar():void { ... }
}
var clazz:Class = Foo;
// ...enter the function (no Foo literal here)
var fun:Function = clazz["bar"]; // PROBLEM: returns null
// later
fun.call(new Foo(), ...);
What is the correct way to do the above? The Java equivalent of what I want to do is:
Method m = Foo.class.getMethod("bar", ...);
m.invoke(new Foo(), ...);
Actual code (with workaround):
class SerClass {
public var className:String;
public var name:String;
private var ser:String = null;
private var unser:Function = null;
public function SerClass(clazz:Class):void {
var type:XML = describeType(clazz开发者_开发技巧);
className = type.@name;
// determine name
name = type.factory.metadata.(@name=="CompactType").arg.(@key=="name").@value;
// find unserializer
var mdesc:XML = XML(type.method.metadata.(@name=="Unserialize")).parent();
if (mdesc is XML) {
unser = clazz[mdesc.@name];
}
// find serializer
var sdesc:XML = XML(type.factory.method.metadata.(@name=="Serialize")).parent();
if (sdesc is XML) {
ser = sdesc.@name;
}
}
public function serialize(obj:Object, ous:ByteArray):void {
if (ser == null) throw new Error(name + " is not serializable");
obj[ser](ous);
}
public function unserialize(ins:ByteArray):Object {
if (unser == null) throw new Error(name + " is not unserializable");
return unser.call(null, ins);
}
}
Here the function bar only exist when your class is instanciated :
var foo:Foo = new Foo()
var fun:Function = foo.bar // <-- here you can get the function from the new instance
if you want to access it directlty you have to make it static:
class Foo {
public static function bar():void{ ... }
}
now you can access your function from the class Foo:
var fun:Function = Foo.bar
or
var clazz:Class = Foo
var fun:Function = clazz["bar"]
I am not sure about what you are intending to do.
However AS3Commons, especially the reflect package have API's that let you work with methods, instances and properties of a class.
There are also API methods to create instances of certain class types on the fly and call their respective methods.
Cheers
It's not
fun.call(new Foo(), ...);
Use instead since no parameters are required for the function
fun.call(clazz);
The first parameter as specified by adobe docs.
An object that specifies the value of thisObject within the function body.
[EDIT]
Forgot to point out you have to instantiate a non-static class with the "new" keyword.
var clazz:Class = new Foo();
[EDIT2]
Ok I played around and think I got what you want.
base.as
package{
public class Base {
public function Base() {
trace('Base constructor')
}
public function someFunc( ){
trace('worked');
}
}
}
//called with
var b:Base = new Base( );// note I am not type casting to Class
var func:Function = b.someFunc;
func.call( );
My workaround is to store the function name instead of the Function
object.
var fun:String = "bar";
// later...
new Foo()[fun](...);
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