代码如下 var o:MyClass = myArray[i] as MyClass;
if(o)
{
//do stuff
} 。 “as”也更符合语言的其他部分(即:“myObject是MyClass”)。 MyClass()方法在处理简单数据类型(int、number、uint、string)时有其他好处--这方面的一些示例如下: var s:String = "89567";
var s2:String = "89 cat";
var n:Number = 1.9897;
var i:int = int(s); // i is = 89567, cast works
var i2:int = int(s2); //Can't convert so i2 is set to 0
var i3:int = int(n); // i = 1
var n2:Number = Number(s2); // fails, n2 = NaN
//when used in equations you'll get very different results
var result:int = int(n) * 10; //result is 10
var result:int = n * 10; //result is 19.89700
var result:int = int(s2) * 10; //result is 0
trace(s2 as Number); //outputs null
trace(s2 as int); //outputs null
trace(Number(s2)); //outputs NaN ... 展开详请