javascript中几种变量类型判断

 

 

Type		typeof	instance	toString
Number	var n = 1	number	false	[object Number]
	var n = Number(1)	number	false	[object Number]
	var n = new Number(1)	object	true	[object Number]
String	var s = "s"	string	false	[object String]
	var s = String("s")	string	false	[object String]
	var s = new String("s")	object	true	[object String]
Boolean	var b = ture	boolean	false	[object Boolean]
	var b = Boolean(true)	boolean	false	[object Boolean]
	var b = new Boolean(true)	object	true	[object Boolean]
null	var nu = n ull	object	false	[object global]
undefined	var u = undefined	undefined	false	[object global]
Array	var a = []	object	true	[object Array]
	var a = Array()	object	true	[object Array]
	var a = new Array()	object	true	[object Array]
RegExp	var r = /^$/	function	false(Function) true(RegExp)	[object RegExp]
	var r = RegExp("^$")	function	false(Function) true(RegExp)	[object RegExp]
	var r = new RegExp("^$")	function	false(Function) true(RegExp)	[object RegExp]
Object	var o = {}	object	true	[object Object]
	var o = Object()	object	true	[object Object]
	var o = new Object()	object	true	[object Object]
Function	var f = function(){}	function	true	[object Function]
	function f(){}	function	true	[object Function]
	var f = new Function()	function	true	[object Function]