谁能告诉我为什么错?急!

Question

if(!zqc){
            <jsp:forward  page="error1.jsp">
       </jsp:forward>
       }
        else 
        {<jsp:forward  page="error2.jsp">
         </jsp:forward>
         }

Answer 1

<%
if(!zqc){
%>
<jsp:forward  page="error1.jsp">
</jsp:forward>
<%}
else 
{
%>
<jsp:forward  page="error2.jsp">
</jsp:forward>
<% }%>

Answer 2

还是错提示:
Param action: Mandatory attribute name missing!
我的全部代码是:
<% Connection con;
    Statement sql; 
    ResultSet rs;
    String loginname=request.getParameter("loginname");
    Boolean zqc=false;
    try
    {
      Class.forName("com.mysql.jdbc.Driver");
    }
    catch(ClassNotFoundException e)
    {
      out.print("类找不到");
    }
    try 
    {  
         con=DriverManager.getConnection("jdbc:mysql://localhost/bookstore?user=root&password=root&useUnicode=true&characterEncoding=GB2312" );
         sql=con.createStatement();
         rs=sql.executeQuery("SELECT * FROM user");
     while(rs.next())
       { if(loginname.equals(rs.getString("loginname")))
          { zqc=true;}
        }
        
        con.close();
        
     }
   catch(SQLException e1) 
   {
      out.print("MYSQL 异常!");
   }
<% Connection con;
    Statement sql; 
    ResultSet rs;
    String loginname=request.getParameter("loginname");
    Boolean zqc=false;
    try
    {
      Class.forName("com.mysql.jdbc.Driver");
    }
    catch(ClassNotFoundException e)
    {
      out.print("类找不到");
    }
    try 
    {  
         con=DriverManager.getConnection("jdbc:mysql://localhost/bookstore?user=root&password=root&useUnicode=true&characterEncoding=GB2312" );
         sql=con.createStatement();
         rs=sql.executeQuery("SELECT * FROM user");
     while(rs.next())
       { if(loginname.equals(rs.getString("loginname")))
          { zqc=true;}
        }
        
        con.close();
        
     }
   catch(SQLException e1) 
   {
      out.print("MYSQL 异常!");
   }
if(!zqc){
%>
<jsp:forward  page="error1.jsp">
</jsp:forward>
<%}
else 
{
%>
<jsp:forward  page="error2.jsp">
</jsp:forward>
<% }%>

Answer 3

修改下:)
<%
if(!zqc){
%>
<jsp:forward  page="error1.jsp"/>
<%}
else 
{
%>
<jsp:forward  page="error2.jsp"/>
<% }%>