Angular 不管你是否相信。例如，BehaviorSubject应该产生类似http://address/cards/topbrand?perpage=25collectionId=id1，id2，id2，id4…..许多后端框架都内置了将key=value1&key

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不管你是否相信。例如，

BehaviorSubject

应该产生类似

http://address/cards/topbrand?perpage=25collectionId=id1，id2，id2，id4…..

许多后端框架都内置了将key=value1&key=value2解析到一个数组中的支持，而不需要额外的代码。通过使用coma方法，您需要创建一个解析器方法。@Jota.Toledo感谢您指出这一点，我不确定是否应该使用该方法。我已经用这两个选项更新了代码，现在您的答案中仍然有“至少它不是最佳实践”。你从哪里弄来的？顺便说一句。我很确定导入“rxjs”要么什么都不做，要么“做得太多了”）我删除了最佳实践部分，并添加了

rxjs

，如果用户决定使用它的其他功能，而不是

可观察的

。是否包含它取决于用户。即

BehaviorSubject

this.selectedItems: SearchItem[]= [
  {"id":"abee232","itemName":"Attractions"},
  {"id":"b6b1a23","itemName":"Artists"},
  {"id":"08a58c8","itemName":"Performing Arts"},
  {"id":"444d047","itemName":"Sports"}
];

  private addRequestOptions(params: SearchItem[]): RequestOptions {
    let options: RequestOptions = new RequestOptions();
      options.params = new URLSearchParams();
    if (params != null) params.forEach((p: SearchItem) => {
      options.params.append("&collectionId", p.id);
    })
    console.log(options)
    return options;
  }

  sortResults(){
        let options: RequestOptions = this.addRequestOptions(this.selectedItems);
        this.pendingCardsService.collectionUuidUrl = 'http://address/cards/topbrands?perPage=25', options;
        this.pendingCardsBrandCollection();
  }

export interface SearchItem {
  id?: string;
  itemName?: string;
}

'http://address/cards/topbrand?perpage=25&collectionId=idValue&collectionId=idValue&collectionId=idValue'

  fetchPendingCardsBrandCollection(ids: SearchItem[], pageSize = '25'):Observable<Card[]> {
    const params = new URLSearchParams();
    params.set('perPage', pageSize);
    ids.forEach(id => params.append('collectionId', id.id));
    return this.http.get(this.collectionUuidUrl, {params: params})
      .map(this.extractData)
  }

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

export interface SomeInterface {
   // Define the properties of the JSON object sent as response from the backend
}

@Injectable()
export class SomeService {
   constructor(private _http: Http){}

   queryElements(ids: string[] = [], pageSize = 25): Observable<SomeInterface>{
      const params = new URLSearchParams();
      params.set('perPage', pageSize); // using set: replace the existing value of the query parameter "perPage" if exist.
      ids.forEach(id => params.append('collectionId', id)); // using append: allows multiple values for the query parameter "collectionId" 
      return 
       this._http.get("http://address/cards/topbrand",{params: params})
         .map(r => r.json())
         .catch(//handle error);
   }
}