02--SpringBoot之参数传递

一：url传参

1.get方式Url传参：@PathVariable

    ////------get方式Url传参
    @GetMapping({"/id/{the_Param}"})
    public String id(@PathVariable("the_Param") Integer id) {
        return "id:" + id;
    }

• 访问：http://localhost:8080/id/1994

2.get方式Url传参：@RequestParam

    ////------get方式Url传参
    @GetMapping(/user)
    public String username(@RequestParam("username") String str) {
        return "username is:" + str;
    }

• 访问：http://localhost:8080/user?username=toly

3.get方式Url传参：@RequestParam+默认参数

    ////------get方式Url传参+默认参数
    @GetMapping("/user_default")
    public String usernameWithDefaultParam(
            @RequestParam(value = "username", defaultValue = "toly1994")
                    String str) {
        return "username is:" + str;
    }

• 访问：http://localhost:8080/user_default

---

二：配置文件传值使用

1.配置文件字段使用

src\main\resources\application-dev.yml

name: black magic
atk: 2500
desc: "name:${name} And atk:${atk}"

toly1994.com.toly01.controller.ParamController

  ////------配置文件字段使用
    @Value("${name}")
    private String lever;
    @Value("${atk}")
    private int atk;
    @Value("${desc}")
    private String desc;

    @GetMapping("/YoGiOh")
    public String paramInRes() {
        return desc;
    }

• 访问：http://localhost:8080/YoGiOh

2.获取配置文件组成员

2-1:写入字段—src\main\resources\application-dev.yml

monster:
  name: blue eyes white Dragon
  atk: 3000

2-2:创建实体类—toly1994.com.toly01.properties.MonsterProperties

@Component //org.springframework.stereotype.Component;
@ConfigurationProperties(prefix = "monster")
public class MonsterProperties {
    private String name;
    private int atk;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAtk() {
        return atk;
    }

    public void setAtk(int atk) {
        this.atk = atk;
    }

    @Override
    public String toString() {
        return "MonsterProperties{" +
                "name='" + name + '\'' +
                ", atk=" + atk +
                '}';
    }
}

2-3:增加方法—toly1994.com.toly01.controller.ParamController

 ////-----获取配置文件组成员
    @RestController
    public class HelloSpringBoot {
        @Autowired //自动创建对象
        private MonsterProperties monster;

        @GetMapping("/monster")
        public String say() {
            return monster.toString();
        }
    }

• 访问：http://localhost:8080/monster