<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>W3Cschool教程(w3cschool.cn)</title> </head> <body> <p>局部变量计数。</p> <button type="button" onclick="myFunction()">计数!</button> <p id="demo">0</p> <script> var add = (function () { var counter = 0; return function () {return counter += 1;} })(); function myFunction(){ document.getElementById("demo").innerHTML = add(); } </script> </body> </html>
原文：https://www.cnblogs.com/sea-stream/p/10259130.html