<!DOCTYPE html> <html lang="zh"> <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>javascript 闭包 面试题</title> </head> <body> <script> function fn(n, o) { console.log(o); return { fn: function(m) { return fn(m, n); } }; } var a = fn(0); //undefined a.fn(1); //0 a.fn(2); //0 a.fn(3); //0 console.log('------------'); var b = fn(0).fn(1).fn(2).fn(3); //undefined,0,1,2 console.log('------------'); var c = fn(0).fn(1); //undefined,0 c.fn(2); //1 c.fn(3); //1 </script> </body> </html>