Angular filter Observable array

Question

I have an Observable array and I want to filter/find the Project by name. When I try to use the filter option it is saying

ProjectService.ts

import { Injectable } from '@angular/core'; import { Project } from "../classes/project"; import { Observable } from 'rxjs/Observable'; import 'rxjs/add/observable/of';  import { Http } from '@angular/http';   @Injectable() export class ProjectService {    private projects: Observable<Project[]>;    constructor(private http: Http) {     this.loadFromServer();   }    getProjects(): Observable<Project[]> {     return this.projects;   }    private loadFromServer() {     this.projects = this.http.get('/api/projects').map(res => res.json());   }    getProjectByName(name: String) {     return this.projects.filter(proj => proj.name === name);   }   } 

Project Class

export class Project {     public name: String;     public miniDesc: String;     public description: String;     public category: String[];     public images: any[]; } 

Answer 1

it should be:

getProjectByName(name: String) {   return this.projects     .map(projects => projects.filter(proj => proj.name === name)); } 

you misunderstood about filter operator. The operator using to filter data return from stream. Your stream return array of object, so you need filter array to get you needed value.

The solution above will return an array after filtered, if you wanna get only one value, using following solution

getProjectByName(name: String) {   return this.projects     .map(projects => {       let fl = projects.filter(proj => proj.name === name);       return (fl.length > 0) ? fl[0] : null;     }); }