public ResponseObject getById(@RequestParam("id") Long id) { return scrapApplyService.getById(id); } export function getById(params){ return rq.post("/api/scrap/apply/getById",params) } 后端这样传值报错,帮忙分析原因

根据你提供的代码，我发现后端控制器方法的请求参数名是`id`，而前端调用API时使用的参数名是`params`。这就导致了后端无法正确获取`id`参数值，从而抛出了缺少必需参数`id`的异常。

为了解决这个问题，你需要确保前端调用API时传递了名为`id`的参数，并且参数值是一个合法的Long类型值。下面是示例代码：

export function getById(id) {
  return rq.post("/api/scrap/apply/getById", {id: id});
}

在示例代码中，我将前端调用API时的参数名改为`id`，并将`id`参数作为POST请求的请求体中的一个属性进行传递。这样后端就可以正确获取`id`参数值了，从而避免了抛出缺少必需参数异常的问题。

相关问题

@RequestMapping("/getById{id}")

This is a Spring MVC annotation that maps a URL endpoint to a method that handles requests with a specific ID parameter. The endpoint URL would be something like "/getById1" or "/getById123", and the method annotated with this mapping would receive the value of "id" as a parameter. For example:

@GetMapping("/getById{id}")
public ResponseEntity<MyObject> getById(@PathVariable("id") Long id) {
    MyObject obj = myService.findById(id);
    return ResponseEntity.ok(obj);
}

In this example, the method "getById" handles GET requests to the endpoint "/getById{id}", where "{id}" is a placeholder for any ID value. The "@PathVariable("id")" annotation maps the "id" parameter to the value in the URL path, and the method calls a service to retrieve the object with that ID. The method returns a ResponseEntity with the object and an HTTP status code of 200 (OK).