fmpq.com
源代码：
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<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Fmpq教程(fmpq.com)</title> <script src="https://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"> </script> <script> $(document).ready(function(){ $("button").click(function(){ alert($("li").size()); }); }); </script> </head> <body> <button>输出li元素的数量</button> <ul> <li>Coffee</li> <li>Milk</li> <li>Soda</li> </ul> </body> </html>
运行结果