@RequestParam注解的使用

-----------参数-------------------------------------------------------------------
RequestParam来映射请求参数

required表示是否必须,默认为true

defaultValue请求参数的默认值

value为接收前台参数的参数名

------------示例------------------------------------------------------------------

@RequestMapping(value = "/testRequestParam")
public String testRequestParam(@RequestParam(value="username")String name,
@RequestParam(value = "age",required = false,defaultValue = "0") int age){
System.out.println("username:"+un+",age,"+age);
return "success";
}

http://localhost:8080/sirdifoa/test/para?username=张三&age=30

结果为：

username:张三，age=30

源码：

/**
* Whether the parameter is required.
* <p>Defaults to {@code true}, leading to an exception being thrown
* if the parameter is missing in the request. Switch this to
* {@code false} if you prefer a {@code null} value if the parameter is
* not present in the request.
* <p>Alternatively, provide a {@link #defaultValue}, which implicitly
* sets this flag to {@code false}.
*/
boolean required() default true;