标签:根据 jsp @param get请求 null font 地址 action err
/** * 如果方法写成了void就跟原来servlet含义是差不多 的 * json */ @RequestMapping("/firstRequest") public void firstRequest(HttpServletRequest request, HttpServletResponse response, HttpSession session) throws IOException { UserInfo info=new UserInfo(); info.setUserid(1); info.setUserName("李四"); /** * json格式传递 */ response.setCharacterEncoding("UTF-8"); String value= JSON.toJSONString(info); response.getWriter().write(value); }
/** * 返回值类型为String时,一般用于返回视图名称 * 1、当方法返回值为null时,默认将请求路径当做视图 forward:/jsp/index.jsp 如果说没有视图解析器,返回值为null携带数据只能用json * 2、当方法返回一个String的字符串时,当字符串为逻辑视图名时只返回视图,如果携带数据则使用request,session或者json * 3、当方法返回值加入forward时代表转发,如果写为redirect:xxxx代表重定向,不是返回视图了,但是不会这样做!! */ @RequestMapping("/secondRequest") public String secondRequest(HttpServletRequest request, HttpServletResponse response){ request.setAttribute("user","张三"); return "forward:/jsp/index.jsp"; }
/** *Object * 1.当方法返回值为null时,默认将请求路径当作视图 jsp/objectRequest.jsp 如果没有视图解析器,如果返回值为null携带数据只能用json * 2.当方法返回值为String类型字符串时,就是视图的逻辑名称 * 3.当返回对象或者集合数据时要使用json格式字符串,可选fashjson手动转换 ,也可以使用jackson自动转换 */ @RequestMapping("/ObjectRequest") @ResponseBody public Object ObjectRequest(){ List<UserInfo> userInfoList=new ArrayList<>(); UserInfo userInfo=new UserInfo(); userInfo.setUserid(111); userInfo.setUserName("鸭头一号"); UserInfo userInfo1=new UserInfo(); userInfo1.setUserid(222); userInfo1.setUserName("鸭头二号"); userInfoList.add(userInfo); userInfoList.add(userInfo1); return userInfoList; }
/** * ModelAndView * @param request 请求对象 * @param response 响应对象 * @return ModelAndView model是用来传递数据用的,view是所需要跳转的页面 */ @RequestMapping("/model") public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response){ ModelAndView modelAndView=new ModelAndView(); //携带给页面数据 modelAndView.addObject("user","鸭头"); //指定跳转页面(视图解析器配置前后缀) modelAndView.setViewName("index"); return modelAndView; }
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>登陆</title> </head> <body> <form action="/fourth/oneRequest" method="post"> 账户:<input type="text" name="userName"/> 密码:<input type="password" name="userpwd"/> <input type="submit" value="登陆"/> </form> </body> </html>
(控制器Controller中的方法参数名称必须和表单元素的name属性值保持一致) @Controller @RequestMapping("/fourth") public class FourthController { /** * 1、请求参数的自动类型转换 * @param userName * @param userpwd * @param model * @return * 控制器Controller中的方法参数名称必须和表单元素的name属性值保持一致 */ @RequestMapping(value = "/oneRequest") public String oneRequest(String userName,String userpwd, Model model){ System.out.println(userName+"\t"+userpwd); model.addAttribute("userCode",userName); return "welcome"; } }
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>登陆</title> </head> <body> <form action="/fourth/twoRequest" method="post"> 账户:<input type="text" name="userName"/> 密码:<input type="password" name="userpwd"/> <input type="submit" value="登陆"/> </form> </body> </html>
(此处必须设置请求类型,否则会显示405错误) /** * 2、RequestMethod.POST 此处必须设置请求类型 否则将会显示405错误 * @param userName * @param userpwd * @param model * @return * 控制器Controller中的方法参数名称必须和表单元素的name属性值保持一致 */ @RequestMapping(value = "/twoRequest",method = RequestMethod.POST) public String twoRequest(String userName,String userpwd, Model model){ System.out.println(userName+"\t"+userpwd); model.addAttribute("userCode",userName); return "welcome"; }
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>登陆</title> </head> <body> <form action="/fourth/formRequest" method="post"> 账户:<input type="text" name="userName"/> 密码:<input type="password" name="userpwd"/> <input type="submit" value="登陆"/> </form> </body> </html>
/** * 3.@RequestParam 注解 * 接收零散参数:装配原则为传递参数名和方法接收参数名一致 * defaultValue默认值 required代表是否必须传递 * @RequestParam 注解 */ @RequestMapping(value = "/formRequest") public String formRequest(@RequestParam(name = "userName",defaultValue = "鸭头") String userName, @RequestParam(name = "userpwd")String userpwd, Model model){ System.out.println(userName+"\t"+userpwd); model.addAttribute("userCode",userName); return "welcome"; }
/** * 4、RESTFUL 风格的参数传递 * get请求时,如果需要传递参数,那么则把不能使用以往的方式?name=xxx&age=yy,但是现在要遵循restful风格,例:xxx/ttt/ddd * 根据地址栏url匹配拿值 使用@PathVariable(name=地址栏中的参数映射) */ @RequestMapping("/restfulRequest/{b}/{d}") public String restfulRequest(@PathVariable(name = "b") String usercode, @PathVariable(name = "d")String userpwd){ System.out.println(usercode+"\t"+userpwd); return "welcome"; }
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>登陆</title> </head> <body> <form action="/fourth/Info" method="post"> 账户:<input type="text" name="userName"/> 密码:<input type="password" name="userpwd"/> <input type="submit" value="登陆"/> </form> </body> </html>
/** * 5、对象参数 */ @RequestMapping(value = "/Info") public String UserRequest(UserInfo info){ System.out.println(info.getUserName()); return "welcome"; }
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>登陆</title> </head> <body> <form action="/fourth/userInfoRequest" method="post"> 老师一号:<input type="text" name="teacher.teacherName"/> <input type="submit" value="登陆"/> </form> </body> </html>
/** * 6、域属性对象参数 */ @RequestMapping(value = "/userInfoRequest") public String UserInfoRequest(UserInfo info){ System.out.println(info.getTeacher().getTeacherName()); return "welcome"; }
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>登陆</title> </head> <body> <form action="/fourth/userInfoRequest" method="post"> 老师二号:<input type="text" name="teacherList[0].teacherName"/> 老师三号:<input type="text" name="teacherList[1].teacherName"/> <input type="submit" value="登陆"/> </form> </body> </html>
/** * 7、域属性集合参数 */ @RequestMapping(value = "/userListRequest") public String UserListRequest(UserInfo info){ System.out.println(info.getTeacherList()); return "welcome"; }
标签:根据 jsp @param get请求 null font 地址 action err
原文地址:https://www.cnblogs.com/Zzzzn/p/11827131.html