1 <!doctype html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Document</title> 6 <script type="text/javascript"> 7 8 (function(w){ 9 w.$ = function(){ 10 alert("======"); 11 }; 12 })(window); 13 14 $();//相当于window.$(); 15 </script> 16 </head> 17 <body> 18 19 </body> 20 </html>
原文：http://www.cnblogs.com/sxmcACM/p/3931724.html
