@RequestParam使用defaultValue属性设置默认值的操作

@RequestParam使用defaultValue属性设置默认值

注意设置必须是string类型的，框架自己会做转换

@RequestParam(value = "page", required = false, defaultValue = "1") Integer page,
@RequestParam(value = "size", required = false) Integer size,

补充：@RequestParam注解的使用说明

自SpringMVC4.2之后，RequestParam内部有4个参数：

1、String name;

2、String value;

3、boolean required;

4、String defaultValue;

源码中name的别名是value，value的别名是name,

所以说name和value两个属性基本是等价的,都是获取从前台传入的参数

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

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

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以上为个人经验，希望能给大家一个参考，也希望大家多多支持服务器之家。如有错误或未考虑完全的地方，望不吝赐教。

原文链接：https://blog.csdn.net/y41992910/article/details/88314233