Question

PrintWriter out=response.getWriter();       
String[] Catg1=request.getParameterValues("Category");
out.println("Category : "+Catg1);

catg1包含null可以任何一个帮助它为什么它将为null。

Answer 1

试试这个：

＆＃13;

<body>
  <h3>Upload Document</h3> 
  Select Category: 
 
     <form action="UploadServlet" method="post">
<select name="rushi" multiple="multiple"> 
  <option value="">Select Category</option>
  <option value="Cat1">Cat1</option> 
  <option value="Cat2">Cat2</option> 
  <option value="other">other</option> 

 
</select>
       </form>
</body> –

＆＃13;

Answer 2

像这样检查......

for(int i=0;i<catg1.length;i++)
       {
           pw.println("<li>"+catg1[i]+"</li>");
       }

下拉值无法从jsp访问servlet

2 个答案: