一个很简单的问题
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www. New Document </title> <meta name="Generator" content="EditPlus"> <meta name="Author" content=""> <meta name="Keywords" content=""> <meta name="Description" content=""> </head> <body> <script language="javascript"> var s=document.getElementsByTagName("body")[0].childNodes[0].value; alert(s);//想输出苹果 </script> <form> <input type="radio" value="苹果"> </form> </body> </html> 想输出“苹果”,也就是单选按钮value属性的值,看看我哪错了,有哪几种方法可以实现?