通过字符串Haxe参考对象 [英] Haxe Reference Object via String

问题描述

在Haxe中，我试图通过变量访问对象的值.在JavaScript中，您可以使用 [] 对其进行访问，但是在Haxe中，此方法将不起作用，并返回错误:

In Haxe, I am trying to access an object's value via a variable. In JavaScript you use [ ] to access it, but in Haxe this doesn't work and comes back with an error:

字符串应为Int

String should be Int

在{x:Int，name:String}上不允许数组访问

Array access is not allowed on { x : Int, name : String }

我需要最后一行代码的帮助:

I need help with the last line of code:

var room = { x: 10, name: 'test' };

trace(room.name);   // this works returns 'test' 

// how do I reference foo to return 'test' as the above result.
var foo = "name";
var results = room[foo];   // need fixing

推荐答案

您要尝试执行的操作称为 反映 API:

What you're trying to do is called Reflection, and the way to do that in Haxe is via the Reflect API:

var results = Reflect.field(room, "name");

如果您想访问 static 字段，则将 Class< T> 作为第一个参数而不是实例:

If you want to access a static field instead, pass the Class<T> as the first argument instead of an instance:

class Foo {
    public static var bar = 0;
}

var bar = Reflect.field(Foo, "bar");

对于具有吸气剂的属性，您需要使用<改为使用href ="https://api.haxe.org/Reflect.html#getProperty" rel ="nofollow noreferrer"> getProperty() .

For properties with a getter, you'll want to use getProperty() instead.

注意:反射通常被认为是不好的做法，因为它会将错误从编译转移到运行时，并且本质上是类型不安全的.通常，有更好的方法来解决问题，但是在没有更多上下文的情况下，很难在这里推荐具体的解决方案.

Note: Reflection is generally considered bad practice as it moves errors from compile- to runtime and is inherently type-unsafe. There are usually better ways to solve a problem, but it's hard to recommend a concrete solution here without more context.

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