instanceof 判断引用类型，typeof判断基本门类

instanceof 判断引用类型，typeof判断基本类型。

//instanceof 判断引用类型，typeof判断基本类型。
	
	function init() {
		//testTypeof();
		testInstanceof();
	}
	window.onload = init;
	
	function testTypeof() {
		var str = "123";
		var num = 123;
		var bool = false;
		var unde_d = undefined;
		var unde_d2;
		var nul = null;
		
		alert(typeof str == "string");//true        注意大小写，js区分大小写
		alert(typeof str == "String");//false
		//alert(typeof str == string);       //错误写法 ，typeof 判断类型需用引号
		alert(typeof num == "number");//true
		alert(typeof bool == "boolean");//true
		alert(typeof unde_d == "undefined");//true
		alert(typeof unde_d2 == "undefined");//true
		alert(typeof nul == "object");  //true
	}
	
	function testInstanceof() {
		var str = "123";
		var obj = new Object();
		var array1 = new Array();
		var func = function() {
			this.name = "marry";
			this.say = function() {
				alert("hello " + this.name);
			}
		}
		var func1 = new func();
		
		alert(str instanceof String);       //flase
		alert(obj instanceof Object);//true
		alert(array1 instanceof Array);//true
		alert(func instanceof Object);//true
		alert(typeof func);//function
		
		alert(func1 instanceof Object);//true
		alert(func1 instanceof func);//true
		alert(typeof func1);//object
	}