prototype.js中的Class.create()的问题
照着网上的例子打得,可就是输出,求高手指教 
  <?xml   version= "1.0 "   encoding= "UTF-8 "   ?>  
  <!DOCTYPE   html   PUBLIC    "-//W3C//DTD   XHTML   1.0   Transitional//EN ">  
  <html   xmlns= "http://www.w3.org/1999/xhtml ">  
  <head>  
  <meta   http-equiv= "Content-Type "   content= "text/html;   charset=UTF-8 "   />  
  <title> Prototype   Number   Example </title>  
  <script   type= "text/javascript "   src= "../../js/prototype.js ">  </script>  
  <script   type= "text/javascript ">  
 var   Animal   =   Class.create(); 
 Animal.prototype   =   { 
       initialize:   function(name,   sound)   { 
             this.name      =   name; 
             this.sound   =   sound; 
       },   
       speak:   function()   { 
             alert(name   +    "   says:    "   +   sound   +    "! "); 
       } 
 };   
 var   snake   =   new   Animal( "Ringneck ",    "hissssssssss "); 
 snake.speak();   
 var   Dog   =   Class.create();   
 Dog.prototype   =   Object.extend(new   Animal(),   { 
       initialize:   function(name)   { 
             this.name      =   name; 
             this.sound   =    "woof "; 
       }       
 });   
 var   fido   =   new   Dog( "Fido "); 
 fido.speak(); 
  </script>  
  </head>  
  <body>      
  </body>  
  </html>
------解决方案--------------------create() ->  Function 
 Returns an function that acts like a Ruby class. 
------解决方案--------------------speak: function() { 
 alert(this.name +  " says:  " + this.sound +  "! "); 
 } 
 };