<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>Document</title> </head> <body> <script> function Star(uname, age) { this.uname = uname; this.age = age; } // In many cases, we need to manually use the constructor property that points back to the original constructor // Star.prototype.sing = function () { // console.log ( 'I can sing'); // }; / / Star.prototype.movie = function () { // console.log ( 'I will turn the movie'); // } Star.prototype = { // If we modified the original prototype object to the prototype object is assigned a objects, you must manually using the constructor refers back to the original constructor constructor: Star, sing: function() { console.log ( ' I can sing ' ); }, movie: function() { console.log ( ' I will turn the movie ' ); } } var LDH = new new Star ( ' Andy ' , 18 is ); var ZXY = new new Star ( ' Jacky ' , 19 ); console.log(Star.prototype); console.log(ldh.__proto__); console.log(Star.prototype.constructor); console.log(ldh.__proto__.constructor); </script> </body> </html>