jquery.form.js上传文件，一点反应都没有。?报错

今天尝试了一下jQuery.form.js插件来进行异步的提交表单上传文件

jsp：

   
  <form style="padding-left: 50px;padding-top: 25px"id="form2" 
             enctype="multipart/form-data"> 

                       选择Excel文件：<input type="file"name="files"id="files"/></p> 
     
                       <input type="button"value="上传"id="bt"/> 
     
        </form>

点击上传按钮的js事件代码：

20

      <script src="JS/jquery-1.8.0.js"type="text/javascript"></script> 
    
      <script src="JS/jquery.form.js"type="text/javascript"></script> 
    
      <script type="text/javascript"> 
    
                      $(function(){ 
    
                          $("#bt").click(function(){ 
    
                              varoptions={ 
    
                                      url:"uploadServlet",    
    
                                      type:"post", 
    
                                      dataType:null,  
    
                                      success:function(mes){ 
    
                                          alert(mes); 
    
                                      } 
    
                                  }; 
    
                                  $("#form2").submit(function() { 
    
                                       $(this).ajaxSubmit(options); 
    
                                       returnfalse; 
    
                                   }); 
    
                          }); 
    
                      }); 
    
 </script>

就是一个简单地上传文件的操作，上传的地址是一个servlet

在servlet中我使用cos上传方式

我在servlet中out.print出OK

servlet：

         publicvoiddoGet(HttpServletRequest request, HttpServletResponse response) 
       
                     throwsServletException, IOException { 
       
                 request.setCharacterEncoding("UTF-8"); 
       
                 response.setContentType("text/html;charset=utf-8"); 
       
                 PrintWriter out=response.getWriter(); 
       
                 String str=""; 
       
                 try{ 
       
                     String ExcelFile=this.getServletContext().getRealPath("ExcelFile")+"\\"; 
       
                     newMultipartRequest(request, ExcelFile,10*1024*1024,"utf-8",newDefaultFileRenamePolicy()) ; 
       
                     str="OK"; 
       
                 }catch(Exception e) { 
       
                     e.printStackTrace(); 
       
                     str="NO"; 
       
                 } 
       
                 out.print(str); 
       
                 out.flush(); 
       
                 out.close(); 
       
             }