对于最新的稳定版本,请使用 Spring Framework 7.0.6!spring-doc.cadn.net.cn

@RequestParam

您可以使用@注解将查询参数绑定到控制器方法参数。以下代码片段展示了使用方法:spring-doc.cadn.net.cn

@Controller
@RequestMapping("/pets")
public class EditPetForm {

	// ...

	@GetMapping
	public String setupForm(@RequestParam("petId") int petId, Model model) { (1)
		Pet pet = this.clinic.loadPet(petId);
		model.addAttribute("pet", pet);
		return "petForm";
	}

	// ...
}
1 使用 @RequestParam
import org.springframework.ui.set

@Controller
@RequestMapping("/pets")
class EditPetForm {

	// ...

	@GetMapping
	fun setupForm(@RequestParam("petId") petId: Int, model: Model): String { (1)
		val pet = clinic.loadPet(petId)
		model["pet"] = pet
		return "petForm"
	}

	// ...
}
1 使用 @RequestParam
The Servlet API “request parameter” concept conflates query parameters, form data, and multiparts into one. However, in WebFlux, each is accessed individually through ServerWebExchange. While @RequestParam binds to query parameters only, you can use data binding to apply query parameters, form data, and multiparts to a command object.

Method parameters that use the @RequestParam annotation are required by default, but you can specify that a method parameter is optional by setting the required flag of a @RequestParam to false or by declaring the argument with a java.util.Optional wrapper.spring-doc.cadn.net.cn

类型转换会自动应用,如果目标方法参数类型不是String。请参见类型转换spring-doc.cadn.net.cn

当一个@RequestParam注解被声明在Map<String, String>MultiValueMap<String, String>参数上时,该映射将填充所有查询参数。spring-doc.cadn.net.cn

请注意,使用 @RequestParam 是可选的——例如,设置其属性。默认情况下,任何简单值类型(由 BeanUtils#isSimpleProperty 确定)且未被任何其他参数解析器解析的参数将被视为带有 @RequestParam 注解。spring-doc.cadn.net.cn