Object.prototype.toString.call 检测对象类型

console.log(Object.prototype.toString.call("jerry"));  //[object String]
console.log(Object.prototype.toString.call(12));  //[object Number]
console.log(Object.prototype.toString.call(true));  //[object Boolean]
console.log(Object.prototype.toString.call(undefined));  //[object Undefined]
console.log(Object.prototype.toString.call(null));  //[object Null]
console.log(Object.prototype.toString.call({name: "jerry"}));  //[object Object]
console.log(Object.prototype.toString.call(function(){}));  //[object Function]
console.log(Object.prototype.toString.call([]));  //[object Array]
console.log(Object.prototype.toString.call(new Date));  //[object Date]
console.log(Object.prototype.toString.call(/\d/));  //[object RegExp]
function Person(){};
console.log(Object.prototype.toString.call(new Person));  //[object Object]