一个简单的JS测试看一个函数对象的属性

一个简单的测试看

function F(){}; f = new F(); for (prop in f) alert(prop);

结果并没有alert什么属性，控制台上可以看到下面的对象。

F
	__proto__: F
		constructor: function F(){}
			arguments: null
			caller: null
			length: 0
			name: "F"
			prototype: F
				constructor: function F(){}
				__proto__: Object
			__proto__: function Empty() {}
				apply: function apply() { [native code] }
				arguments: null
				bind: function bind() { [native code] }
				call: function call() { [native code] }
				caller: null
				constructor: function Function() { [native code] }
				length: 0
				name: "Empty"
				toString: function toString() { [native code] }
				__proto__: Object
				<function scope>
			<function scope>
				Global: Window
		__proto__: Object
			__defineGetter__: function __defineGetter__() { [native code] }
			__defineSetter__: function __defineSetter__() { [native code] }
			__lookupGetter__: function __lookupGetter__() { [native code] }
			__lookupSetter__: function __lookupSetter__() { [native code] }
			constructor: function Object() { [native code] }
			hasOwnProperty: function hasOwnProperty() { [native code] }
			isPrototypeOf: function isPrototypeOf() { [native code] }
			propertyIsEnumerable: function propertyIsEnumerable() { [native code] }
			toLocaleString: function toLocaleString() { [native code] }
			toString: function toString() { [native code] }
			valueOf: function valueOf() { [native code] }

改改上面的代码如下：

function F(){this.attr="test"}; f = new F(); for (prop in f) alert(prop);

这是就会alert出attr.