Spring MVC 的请求参数获取

Spring MVC 的请求参数获取

1.通过@PathVariabl注解获取路径中传递参数

 @RequestMapping(value = "/{id}/{str}")
 public ModelAndView helloWorld(@PathVariable String id,
         @PathVariable String str) {
     System.out.println(id);
     System.out.println(str);
     return new ModelAndView("/helloWorld");
 }

2.用@ModelAttribute注解获取POST请求的FORM表单数据

 <form method="post" action="hao.do">
     a: <input id="a" type="text" name="a" />
     b: <input id="b" type="text" name="b" />
        <input type="submit" value="Submit" />
 </form>

JAVA pojo

 public class Pojo{
  private String a;
  private int b;
  ....

3. 直接用 HttpServletRequest获取

 @RequestMapping(method = RequestMethod.GET)
 public String get(HttpServletRequest request, HttpServletResponse response) {
     System.out.println(request.getParameter("a"));
     return "helloWorld";
 }

4.用注解@RequestParam绑定请求参数a到变量a
当请求参数a不存在时会有异常发生,可以通过设置属性required=false解决,
例如: @RequestParam(value="a", required=false)

 @RequestMapping(value = "/requestParam", method = RequestMethod.GET)
 public String setupForm(@RequestParam("a") String a, ModelMap model) {
     System.out.println(a);
     return "helloWorld";
 }