Question

我正在尝试从Angular前端的Laravel API访问数据。要接收所需的数据，我必须将“ id”作为POST发送到URL，URL进而查询数据库并将结果作为JSON返回。使用POSTMAN和其他API测试器工具，我已验证端点正常运行。当我尝试从Angular发送POST请求时，我没有在Laravel API上收到POST数据，并且出现以下错误。

请注意，我已从代码中删除了实际的网址

(1/1) ErrorException
Trying to get property of non-object

in ServiceRequestController.php line 209
at HandleExceptions->handleError(8, 'Trying to get property of non-object', '/home/removed_name/public_html/KoiKaam/app/Http/Controllers/ServiceRequestController.php', 209, array('request' => object(Request), 'serviceRequests' => object(Collection), 'id' => null, 'category' => null, 'cats' => object(Collection), 'cat' => null))
in ServiceRequestController.php line 209

在POSTMAN和Android应用程序上测试的实际结果应为this (a screenshot of the result)

这是我用来获取结果的角度服务的代码

import { Http, Headers, RequestOptions } from '@angular/http';
import { Injectable } from '@angular/core';
import { Observable } from 'rxjs/Observable';

import { HttpClient, HttpHeaders, HttpResponse } from '@angular/common/http';
import { BuyDeliverRequests } from '../classes/buy-deliver-requests';


const httpOptions = {
  headers: new HttpHeaders({ 'Content-Type': 'application/json' })
};
const httpPostOptions = {
  headers: new HttpHeaders().set('Content-Type', 'application/x-www-form-urlencoded')
};

@Injectable()
export class BuyDeliverRequestsService {
    private url = 'http://removed_name/KoiKaam/public/api/serviceRequestByCategory'
  constructor(private http: HttpClient) { }


  getBuyDeliverServices(serverResponse: BuyDeliverRequests) {

      return this.http.post(this.url, {id: 1},  httpPostOptions).subscribe(
        data => { serverResponse = data.data; console.log(data); },
        err => console.log(err),
        () => console.log('Successful')
      );
  }
}

这是URL /端点转到的功能，用于获取结果：

 /*this function returns all rows of service request wrt category with their picture paths from service request pictures table
    and bids on that request request*/
    public function showServiceRequestbyCategory(Request $request)
    {
        $serviceRequests = new Collection();
        $id = $request->id; 

        $category = Category::find($id);
        $this->categories->push($category);
        $cats = $this->getChilds($id);
        try{
            foreach ($cats as $cat){
                $srv = $this->getServiceRequest($cat->id); //This is line 209 from the error
                foreach ($srv as $service){
                    $serviceRequests->push($service);
                }
            }

            $response["message"] = "Post Created Successfully";
            $response["error"] = false;
            $response["data"] = $serviceRequests;
            return json_encode($response);
        }
        catch (QueryException $e){
            $response["message"] = $e->errorInfo[2];
            $response["error"] = true;
            $response["sja"] = "2nd";
            return json_encode($response);
        }
    }

以下是Laravel识别错误的行上正在调用的函数

private function getServiceRequest($category_id){
    try{
        $serviceRequest = ServiceRequest::where([['category_id','=', $category_id],
            ['in_process_flag', '=', false]])->paginate(5);
        if($serviceRequest){
            return $serviceRequest;
        }
    }
    catch(QueryException $e){

    }
}

Answer 1

经过大量的搜索，终于指出了问题并找到了解决方法

问题

当Angular 5通过POST发送数据时，它以JSON形式发送。我在Laravel End上的控制器期望使用FORM数据，可以通过$request->id

进行访问

解决方案

有两种解决方法。在Angular一侧或Laravel一侧。

Laravel

这真的很简单，我们首先需要将其存储在数组中，而不是直接访问$request

$data= $request->json()->all();

然后我们可以使用$data作为关联数组来获取所需的数据，例如如果我想使用 id ，我会

$id= $data['id'];，然后根据需要使用$ id

角度

我们首先需要序列化存储数据的对象，然后再将其发布到Laravel后端。 jQuery为此具有自己的功能$.param()，但是由于我们使用的是angular，因此我发现了一个自定义函数，其功能相同。

formatData(data) {
let returnData = '';
let count = 0;
for (let i in data) {
  if (count == 0) {
    returnData += i + '=' + data[i];
  } else {
    returnData += '&' + i + '=' + data[i];
  }
  count = count + 1;
}
return returnData;
}

因此，要发送数据，我必须如下编辑Service类功能

getServicesByCategory(category_id: number) {
let data = {id: category_id};
let body = this.formatData(data);
  return this.http.post(this.url, body,  httpPostOptions);
}

在另一个问题here

上找到了此功能

ErrorException：从Angular 5 Service向Laravel 5.4 API发送POST请求时，'试图获取非对象的属性'

1 个答案:

问题

解决方案