如何从一个actionscript类的实例中获取Class
?
在Python中,可以使用x.__class__
;在Java中,可以使用x.getClass();
。
我知道有某些可怕的黑科技可以做到这一点,但我正在寻找一种内置的语言功能,或者至少是基于可靠东西构建的库程序。
如何从一个actionscript类的实例中获取Class
?
在Python中,可以使用x.__class__
;在Java中,可以使用x.getClass();
。
我知道有某些可怕的黑科技可以做到这一点,但我正在寻找一种内置的语言功能,或者至少是基于可靠东西构建的库程序。
var myClass:Class = Object(myObj).constructor;
var sprite:Sprite = new Sprite();
var xml:XML = new XML();
var testInt:int = 2;
var testClass:TestClass = new TestClass();
var testAnon:Object = {};
trace("classname 1 = " + getQualifiedClassName(sprite));
trace("myclass 1 = " + getDefinitionByName(getQualifiedClassName(sprite)));
trace("constructor a 1 = " + Object(sprite).constructor);
trace("constructor a 1 = " + (Object(sprite).constructor as Class));
trace("constructor b 1 = " + sprite["constructor"]);
trace("constructor b 1 = " + (sprite["constructor"] as Class));
trace("...");
trace("classname 2 = " + getQualifiedClassName(xml));
trace("myclass 2 = " + getDefinitionByName(getQualifiedClassName(xml)));
trace("constructor a 2 = " + Object(xml).constructor);
trace("constructor a 2 = " + (Object(xml).constructor as Class));
trace("constructor b 2 = " + xml["constructor"]);
trace("constructor b 2 = " + (xml["constructor"] as Class));
trace("...");
trace("classname 3 = " + getQualifiedClassName(testInt));
trace("myclass 3 = " + getDefinitionByName(getQualifiedClassName(testInt)));
trace("constructor a 3 = " + Object(testInt).constructor);
trace("constructor a 3 = " + (Object(testInt).constructor as Class));
trace("constructor b 3 = " + testInt["constructor"]);
trace("constructor b 3 = " + (testInt["constructor"] as Class));
trace("...");
trace("classname 4 = " + getQualifiedClassName(testClass));
trace("myclass 4 = " + getDefinitionByName(getQualifiedClassName(testClass)));
trace("constructor a 4 = " + Object(testClass).constructor);
trace("constructor a 4 = " + (Object(testClass).constructor as Class));
trace("constructor b 4 = " + testClass["constructor"]);
trace("constructor b 4 = " + (testClass["constructor"] as Class));
trace("...");
trace("classname 5 = " + getQualifiedClassName(testAnon));
trace("myclass 5 = " + getDefinitionByName(getQualifiedClassName(testAnon)));
trace("constructor a 5 = " + Object(testAnon).constructor);
trace("constructor a 5 = " + (Object(testAnon).constructor as Class));
trace("constructor b 5 = " + testAnon["constructor"]);
trace("constructor b 5 = " + (testAnon["constructor"] as Class));
trace("...");
假设有以下定义的TestClass
:
package
{
public class TestClass
{
}
}
结果:
classname 1 = flash.display::Sprite
myclass 1 = [class Sprite]
constructor a 1 = [class Sprite]
constructor a 1 = [class Sprite]
constructor b 1 = [class Sprite]
constructor b 1 = [class Sprite]
...
classname 2 = XML
myclass 2 = [class XML]
constructor a 2 =
constructor a 2 = null
constructor b 2 =
constructor b 2 = null
...
classname 3 = int
myclass 3 = [class int]
constructor a 3 = [class Number]
constructor a 3 = [class Number]
constructor b 3 = [class Number]
constructor b 3 = [class Number]
...
classname 4 = src::TestClass
myclass 4 = [class TestClass]
constructor a 4 = [class TestClass]
constructor a 4 = [class TestClass]
constructor b 4 = [class TestClass]
constructor b 4 = [class TestClass]
...
classname 5 = Object
myclass 5 = [class Object]
constructor a 5 = [class Object]
constructor a 5 = [class Object]
constructor b 5 = [class Object]
constructor b 5 = [class Object]
...
在目前的测试之外,有足够的理由使用 getDefinitionByName
方法,而不是constructor
方法。 getDefinitionByName
方法允许:
现在可能会比较慢,但未来由Adobe推出的改进可能会解决速度问题。
例如,以前在for循环中,uint
要比int
慢得多,因此设置了大量的转换代码以使用更快的int
。这是一个相当简单的问题,所以Adobe进行了修复,现在有很多代码需要跳过一些不必要的步骤来实现过时的目标。
由于getDefinitionByName
方法在所有情况下都能正确工作,因此应该使用该方法编写代码,然后努力让Adobe解决速度问题。
您不能这样做的任何原因吗?
var s:Sprite = new flash.display.Sprite();
var className:String = flash.utils.getQualifiedClassName( s );
var myClass:Class = flash.utils.getDefinitionByName( className ) as Class;
trace(className ); // flash.display::Sprite
trace(myClass); // [class Sprite]
var s2 = new myClass();
trace(s2); // [object Sprite]
我不知道避免通过字符串来回传递的方法,但这应该足够有效。