angular 4 Error: Uncaught (in promise): Error: No provider for ConnectionBackend! while injecting Jsonp

问题:

When i am trying to inject Jsonp, i am seeing this error

Exception: Call to Node module failed with error: Error: Uncaught (in promise): Error: No provider for ConnectionBackend! Error: No provider for ConnectionBackend! at Error (native)

My home.component.ts file

import { NgModule, Component, Injectable } from '@angular/core'; import { HttpModule, JsonpModule, Jsonp, Response, URLSearchParams, Headers, RequestOptions } from '@angular/http';  @Component({     selector: 'home',     templateUrl: './home.component.html',     providers: [HttpModule, JsonpModule, Jsonp] })  @Injectable() export class HomeComponent {     public jsonp: Jsonp;     constructor(jsonp: Jsonp) {         this.jsonp = jsonp;     } 

Please help me in resolving this issue.

回答1:

providers array can only have Injectable not modules

providers: [HttpModule, JsonpModule, Jsonp] 

should be

providers: [Jsonp] 

Also make sure you should include HttpModule, JsonpModule in imports NgModule of your AppModule

回答2:

You miss import JsonpModule in your app.module.ts, in the next lines I show you, where you should import JsonpModule .

app.module.ts

    import { BrowserModule } from '@angular/platform-browser';     import { NgModule } from '@angular/core';     import { JsonpModule } from '@angular/http';     import { HttpModule }    from '@angular/http';     import { HomeComponent }  from './yourComponentFolder/home.component'      @NgModule({   declarations: [     AppComponent,     HomeComponent,     ],   imports: [     BrowserModule,     HttpModule,     JsonpModule   ],   providers: [],   bootstrap: [AppComponent] }) export class AppModule { }

文章来源: angular 4 Error: Uncaught (in promise): Error: No provider for ConnectionBackend! while injecting Jsonp