AS3 as vs Class()

Question

我不完全理解这个示例中这两种类型转换方法的优点/缺点:

for each(var i:DisplayObject in _display)
{
    trace(i as Sprite);
    trace(Sprite(i));
}

是否有针对此的建议？我总是Class()像后一个例子一样包裹但as有时更容易阅读.

Answer 1

据我所知,不同之处在于TypeError.

var o:Object = "test";

trace( o as MovieClip ); // displays: null
trace ( MovieClip ( o ) ); // generates a TypeError