<html:select 怎样保持下拉框里值

补充一下
--------------------------leftAction-------------------------- 
public   class   LeftAction   extends   Action 
{ 
          public   ActionForward   execute(ActionMapping   mapping,   
                                                                    ActionForm   form,   
                                                                    HttpServletRequest   request,   
                                                                    HttpServletResponse   response) 
{ 
LeftForm   leftForm   =   (LeftForm)   form; 
Vector   rs   =   new   Vector(2); 
rs.add(new   LabelValueBean( "CSDN ",   "001 ")); 
rs.add(new   LabelValueBean( "百度 ",   "002 ")); request.setAttribute( "custList ",   rs); 
return   (new   ActionForward(mapping.getInput())); 
} 
}