<!DOCTYPE html>charset="utf-8"W3Cschool教程(w3cschool.cn)constructor 属性返回变量或对象的构造函数。id="demo"document.getElementById("demo").innerHTML ="john".constructor + "<br>" +(3.14).constructor + "<br>" +false.constructor + "<br>" +[1,2,3,4].constructor + "<br>" +{name:'john', age:34}.constructor + "<br>" +new Date().constructor + "<br>" +function () {}.constructor;