AS3:调用静态类方法——类名和方法名都是字符串 [英] AS3: call a static class method - class and method names are strings

问题描述

我有一个丑陋的问题.我有两个字符串变量(className 和 staticMethod)存储一个类的名称，它是我必须调用的静态方法:

I have an ugly problem. I have two string variables (className and staticMethod) store the name of a class and it's static method I have to call:

package {
 import flash.display.Sprite;
 import flash.utils.getDefinitionByName;
 import flash.utils.getQualifiedClassName;

 public class ClassPlay extends Sprite {

  public function ClassPlay() {
   new Foo();
   var className:String = 'Foo';
   var staticMethod:String = 'bar';
   var classClass:Class = getDefinitionByName(className) as Class;
   try {
    classClass[staticMethod]();
   } catch (e:Error) {}
  }
 }
}

这是主题类:

package {
 public class Foo {
  public static function bar():void {trace('Foo.bar() was called.');}
 }
}

它完美地工作.注释掉这行(第 9 行)时的问题:

It works just perfectly. The problem when you comment out this (9th) line:

// new Foo();

没有这一行，它会以异常退出:

Without this line it exits with an exception:

ReferenceError: Error #1065: Variable Foo is not defined.

没有那个实例我怎么能做到这一点?如果这是不可能的，有没有办法从字符串变量实例化类?或者如果这仍然是一个不好的做法，你会怎么做?(我必须使用这两个未知的字符串变量.)

How could I do this without that instantiation? If that is impossible, is there a way to instantiate the class from the string variable? Or if it's still a bad practice, how would you do that? (I have to work with those two unknown string variable.)

提前致谢.

推荐答案

原因是编译器会剔除不必要的类 - 如果你在某处没有显式引用 Foo 类，它将不会出现在您的最终申请中.

The reason is that the compiler will strip out unnecessary classes - if you don't have an explicit reference to the class Foo somewhere, it won't be present in your final application.

您可以在其他地方引用并仍然强制加载它 - 例如，对类的引用的静态数组.

You could the reference elsewhere and still force it to be loaded - for example, a static array of references to the classes.

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