这个cURL请求如何工作？

Question

我希望每次在$fields循环中创建for时发送 $registrationIDs = array("a","b","c","D", "E","f","g"); $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt( $ch, CURLOPT_POST, true ); curl_setopt( $ch, CURLOPT_HTTPHEADER, $headers); curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true ); $result1 = curl_exec($ch); curl_close($ch); $push_devices_limit =2; if (sizeof($registrationIDs) > $push_devices_limit ) { for ($i = 0; $i <= sizeof($registrationIDs); $i+= $push_devices_limit) { $idArr = array_slice($registrationIDs, $i, $i+$push_devices_limit); $fields = array( 'registration_ids' => $idArr, 'data' => array("message" => $message), ); } curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($fields)); $result = curl_exec($ch); curl_close($ch); } ，并且每次都不关闭连接时发送到服务器。由于我是PHP的新手，我不知道cURL请求是如何工作的，有人可以用下面的代码帮助我 -

import { Injectable } from '@angular/core';
import { Http, Response, URLSearchParams } from '@angular/http';
import { Observable } from 'rxjs/Rx';
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/catch';

import { AuthInfoInterface } from '../interfaces/authentication';

@Injectable()
export class AuthenticationService {
  private url: string = 'api/authentication';

  constructor (private http: Http) {}

  get(): Observable<AuthInfoInterface> {
    let params = new URLSearchParams();

    params.set("redirect", "false");
    params.set("passive", "true");
    return this.http.get(this.url, {search: params})
      .map((res: Response) => res.json())
      .catch(this.handleError);
  }
  handleError(error: any) {
    let errorMsg = error.message || 'Server Error!';
    console.error(errorMsg);
    return Observable.throw(errorMsg);
  }
}