undefined post error in http angular2 - http

I am trying to post the data to database,but i am getting the error "cannot read the property 'post' of undefined".I am trying to learn angular2 can someone help me.
import {Component} from '#angular/component'
import {FormBuilder, Validators, ControlGroup, FORM_DIRECTIVES} from '#angular/common';
import {HTTP_PROVIDERS, Http, Response} from '#angular/http';
#Component({
selector: 'profile-form',
directives: [FORM_DIRECTIVES],
templateUrl: './components/profile/profile.html',
providers: [FormBuilder, HTTP_PROVIDERS]
})
export class Profile {
data;
form;
constructor(private http: Http) {}
onSubmit(): void {
this.http.post(
'http://localhost/a2server/index.php/profile/addprofile',
JSON.stringify({
firstname: 'bar',
lastname: 'foo'
}))
.subscribe((res: Response) => {
this.data = res.json();
});
}
}

Related

Angular 2 not able to call Custom Web Api using asp.net MVC 5 Web Api

I have a problem calling Custom Web Api in asp.net MVC 5.The following is my code for Web Api Controller and angular js 2.
[Route("api/email/detail/{id:int}"), HttpGet]
public async Task<IHttpActionResult> EmailDetail(int id)
{
return Ok();
}
The code for angular app.routing.ts is as follows:
import { ModuleWithProviders } from '#angular/core';
import { Routes, RouterModule } from '#angular/router';
import { HomeComponent } from './components/home.component';
import { UserComponent } from './components/user.component';
import { EmailComponent } from './components/email.component';
import { EmailDetail } from './components/email.detail';
const appRoutes: Routes = [
{ path: 'App/Template', redirectTo: 'home', pathMatch: 'full' },
{ path: 'home', component: HomeComponent },
{ path: 'user', component: UserComponent },
{ path: 'detail/:id', component: EmailDetail },
{ path: 'email', component: EmailComponent },
//{ path: 'detail', component: EmailDetail},
];
export const routing: ModuleWithProviders = RouterModule.forRoot(appRoutes);
Code for email.detail.ts is as follows:
import { Component, OnInit, ViewChild } from '#angular/core';
import { ActivatedRoute } from '#angular/router';
import { UserService } from '../Service/user.service';
import { IEmail } from '../Models/user';
import { Http, Response, Headers, RequestOptions } from '#angular/http';
#Component({
templateUrl: 'About/Template/Detail'
})
export class EmailDetail implements OnInit {
private emailId: number;
private email: IEmail
constructor(private _userService: UserService, private _http: Http,
private route: ActivatedRoute) {
}
ngOnInit(): void {
this._http.get("api/email/detail/1992").subscribe(data => {
// Read the result field from the JSON response.
});
}
}
The error I get in the console is as follows:
The api call is http://localhost:16552/detail/api/email/detail/1992 and detail is getting prepended which is preventing from calling the api controller.
useHash solved the problem and its working fine now.

angular2 http.post The original address and destination address are together

Angular2 http.post(http://127.0.0.1:555)
Chrome developer network show
post "http://127.0.0.1:4444/127.0.0.1:5555" is not found
"http://127.0.0.1:5555" is node server
"http://127.0.0.1:4444" is angular2 server
Why the two stack together?
post component
import { Component, OnInit } from '#angular/core';
import {ActivatedRoute, Router } from '#angular/router';
import {PostDetailService} from './post-detail.service';
#Component({
selector: 'app-post-detail',
templateUrl: './post-detail.component.html',
styleUrls: ['./post-detail.component.scss']
})
export class PostDetailComponent implements OnInit {
postDetail= {
title: '',
userName: '',
postWriteTime: 0,
readTimes: 0,
commentTimes: 0
};
opts = {
url: 'http:127.0.0.1:5555/postDetail',
body: '',
};
constructor(private router: Router, private activateRoute: ActivatedRoute, private postDetailService: PostDetailService) { }
ngOnInit() {
this.activateRoute.params.subscribe((params) => {
this.opts.body = params['postId'];
console.log(params, 'params');
});
this.getPostDetailById();
}
getPostDetailById() {
this.postDetailService.getPostDetail(this.opts).subscribe(
res => {
console.log(res, 'res');
},
err => console.log(err),
() => console.log("complete"));
}
}
import { Injectable } from '#angular/core';
import {Http, Response} from '#angular/http';
import {Observable} from 'rxjs/Rx';
#Injectable()
export class PostDetailService {
constructor(private http: Http) {}
getPostDetail(opts): Observable<any> {
console.log(opts, 'opts');
return this.http.post(opts.url, opts.body).
map((res: Response) => res.json())
.catch((error: any) => Observable.throw(error || 'Server error'));
}
}
The url should be
url: 'http://127.0.0.1:5555/postDetail',
instead of
url: 'http:127.0.0.1:5555/postDetail',

Angular2.1 Cannot read property 'get' of undefined

So, I'm currently trying to send a HTTP request, I'm doing everything exactly like in official guide and it's wont work (as usual when you make deal with Angular2)
Here is my app.module
import { NgModule } from '#angular/core';
import { BrowserModule } from '#angular/platform-browser';
import { RouterModule, Routes } from '#angular/router';
import { HttpModule, JsonpModule } from '#angular/http';
import { AppComponent } from './app.component';
import { PageComponent } from './modules/Affiliate/affiliate.component';
import { NotFoundComponent } from './not-found.component';
const routes: Routes =
[
{ path: 'page', component: PageComponent },
{ path: '404', component: NotFoundComponent },
{ path: '**', redirectTo: '404' }
];
#NgModule({
imports: [
BrowserModule,
RouterModule.forRoot(routes),
HttpModule,
JsonpModule
],
declarations: [
AppComponent,
],
bootstrap: [ AppComponent ]
})
export class AppModule { }
And here is my service, where I'm trying to send a http request
import { Injectable } from '#angular/core';
import { Headers, Http } from '#angular/http';
import 'rxjs/add/operator/toPromise';
#Injectable()
export class GridService {
constructor(private http: Http) { }
getTableRaws(url): Promise<any> {
return this.http.get(url)
.toPromise()
.then(response => response.json().data as any)
.catch(this.handleError);
}
private handleError(error: any): Promise<any> {
console.error('An error occurred', error);
return Promise.reject(error.message || error);
}
}
Any ideas, please
Following the docs, I guess you missed the data type for the url param:
getTableRaws(url: string): Promise<any> {
...
}
UPDATE:
You need to add GridService as a provider in app.module. Refer to this SO answer.
If you have made these changes then update your code in the question and also provide the contents of app.component here.
Here is the solution that works for me:
constructor(#Inject(Http) private http: Http) {}

Navigating between same components using Back/Forward browser buttons does not work

Hi I'm having trouble navigating with a browsers back/forward buttons. It only occurs when navigating between routes that share the same component via route parameters.
I have an application that lists lots of animals. Every time I navigate to example.com/animal/cat or example.com/animal/dog, a Http Get request is made to a restful Api which returns the relevant data. If I navigate to /animal/cat then to /animal/dog everything seems ok. The problem starts when I click on the browsers Back Button to go back to /animal/cat. Instead of loading the data for the cat, the URL changes but the data is still listed for the dog. I'm using router 3.0.0-beta.2 with RC4.
heres my animals details.component page:
import { Component, OnInit, OnDestroy } from '#angular/core';
import { ROUTER_DIRECTIVES, ActivatedRoute, Router } from '#angular/router';
import { Response } from '#angular/http';
import { Subscription } from 'rxjs/Rx';
import { DataService } from '../../data.service';
#Component({
moduleId: module.id,
selector: 'animal-details',
templateUrl: 'animal-details.component.html',
styleUrls: ['animal-details.component.css'],
directives:[ROUTER_DIRECTIVES]
})
export class AnimalDetailsComponent implements OnInit, OnDestroy {
constructor(private activatedRoute: ActivatedRoute, private dataService: DataService, private router: Router) {
}
private subscription: Subscription;
animal = {};
link: string;
table = 'animal/';
private url = '?related=family_by_link';
ngOnInit() {
this.subscription = this.activatedRoute.params.subscribe(
(param: any) => this.link = param['link']
);
this.dataService.getData(this.table, this.link, this.url)
.map((response: Response) => response.json())
.subscribe(
(data: any) => {this.animal = data},
err => { console.log('error404') }
);
};
nextData(){
this.dataService.getData(this.table, this.link, this.url)
.map((response: Response) => response.json())
.subscribe(
(data: any) => {this.animal = data},
err => { console.log('error404') }
);
window.scroll(0,0);
};
ngOnDestroy() {
this.subscription.unsubscribe();
};
}
I use the getData() method when navigating between animals on the same component. My AnimalComponentDetails html:
<div class="row">
<div class="col-sm-6 col-md-4 col-lg-3 text-xs-center" *ngFor="let family of animal.family_by_link" (click)="nextData()">
<a [routerLink]="['/animal', family.ani_link]">
<img src="/images/animal/{{family.ani_link}}.png">
<p>{{family.name}}</p>
</a>
</div>
Heres my DataService:
import { Injectable } from '#angular/core';
import { Http, Response } from '#angular/http';
import { Subscription, Observable } from 'rxjs/Rx';
import 'rxjs/add/operator/map'
#Injectable()
export class DataService {
constructor(private dataService: Http) {
}
urlprefix = 'http://123.123.123.123/api/v2/_table/';
api = '&api_key=7201521drgdc71';
getData(table, link, url): Observable<any> {
return this.dataService.get(this.urlprefix + table + link + url +this.api);
}
}
my app.routes:
import { provideRouter } from '#angular/router';
import { AnimalComponent } from './animal/animal.component';
import { AnimalDetailsComponent } from './animal/animal-details/animal-details.component'
{ path: '', component: HomeComponent },
{ path: 'animal', component: AnimalComponent },
{ path: 'animal/:link', component: AnimalDetailsComponent },
{ path: '**', redirectedTo: 'error404', component: Error404Component }
];
export const APP_ROUTES_PROVIDER = [
provideRouter(APP_ROUTES)
];
And my boot:
import { bootstrap } from '#angular/platform-browser-dynamic';
import { enableProdMode } from '#angular/core';
import { AppComponent, environment } from './app/';
import { HTTP_PROVIDERS } from '#angular/http';
import { APP_ROUTES_PROVIDER } from './app/app.routes'
if (environment.production) {
enableProdMode();
}
bootstrap(AppComponent, [APP_ROUTES_PROVIDER, HTTP_PROVIDERS]);
Chrome's Network indicates when I navigate back or forward on the same component between animal/:cat and animal/:dog via browser buttons, no new Http requests are made unless I change to a different component.
This is the last bug I'm down too. Would appreciate any help, thanks!

How to catch exception correctly from http.request()?

Part of my code:
import {Injectable} from 'angular2/core';
import {Http, Headers, Request, Response} from 'angular2/http';
import {Observable} from 'rxjs/Observable';
import 'rxjs/add/operator/map';
#Injectable()
export class myClass {
constructor(protected http: Http) {}
public myMethod() {
let request = new Request({
method: "GET",
url: "http://my_url"
});
return this.http.request(request)
.map(res => res.json())
.catch(this.handleError); // Trouble line.
// Without this line code works perfectly.
}
public handleError(error: Response) {
console.error(error);
return Observable.throw(error.json().error || 'Server error');
}
}
myMethod() produces exception in console of browser:
ORIGINAL EXCEPTION: TypeError: this.http.request(...).map(...).catch is not a function
Perhaps you can try adding this in your imports:
import 'rxjs/add/operator/catch';
You can also do:
return this.http.request(request)
.map(res => res.json())
.subscribe(
data => console.log(data),
err => console.log(err),
() => console.log('yay')
);
Per comments:
EXCEPTION: TypeError: Observable_1.Observable.throw is not a function
Similarly, for that, you can use:
import 'rxjs/add/observable/throw';
New service updated to use the HttpClientModule and RxJS v5.5.x:
import { Injectable } from '#angular/core';
import { HttpClient, HttpErrorResponse } from '#angular/common/http';
import { Observable } from 'rxjs/Observable';
import { catchError, tap } from 'rxjs/operators';
import { SomeClassOrInterface} from './interfaces';
import 'rxjs/add/observable/throw';
#Injectable()
export class MyService {
url = 'http://my_url';
constructor(private _http:HttpClient) {}
private handleError(operation: String) {
return (err: any) => {
let errMsg = `error in ${operation}() retrieving ${this.url}`;
console.log(`${errMsg}:`, err)
if(err instanceof HttpErrorResponse) {
// you could extract more info about the error if you want, e.g.:
console.log(`status: ${err.status}, ${err.statusText}`);
// errMsg = ...
}
return Observable.throw(errMsg);
}
}
// public API
public getData() : Observable<SomeClassOrInterface> {
// HttpClient.get() returns the body of the response as an untyped JSON object.
// We specify the type as SomeClassOrInterfaceto get a typed result.
return this._http.get<SomeClassOrInterface>(this.url)
.pipe(
tap(data => console.log('server data:', data)),
catchError(this.handleError('getData'))
);
}
Old service, which uses the deprecated HttpModule:
import {Injectable} from 'angular2/core';
import {Http, Response, Request} from 'angular2/http';
import {Observable} from 'rxjs/Observable';
import 'rxjs/add/observable/throw';
//import 'rxjs/Rx'; // use this line if you want to be lazy, otherwise:
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/do'; // debug
import 'rxjs/add/operator/catch';
#Injectable()
export class MyService {
constructor(private _http:Http) {}
private _serverError(err: any) {
console.log('sever error:', err); // debug
if(err instanceof Response) {
return Observable.throw(err.json().error || 'backend server error');
// if you're using lite-server, use the following line
// instead of the line above:
//return Observable.throw(err.text() || 'backend server error');
}
return Observable.throw(err || 'backend server error');
}
private _request = new Request({
method: "GET",
// change url to "./data/data.junk" to generate an error
url: "./data/data.json"
});
// public API
public getData() {
return this._http.request(this._request)
// modify file data.json to contain invalid JSON to have .json() raise an error
.map(res => res.json()) // could raise an error if invalid JSON
.do(data => console.log('server data:', data)) // debug
.catch(this._serverError);
}
}
I use .do() (now .tap()) for debugging.
When there is a server error, the body of the Response object I get from the server I'm using (lite-server) contains just text, hence the reason I use err.text() above rather than err.json().error. You may need to adjust that line for your server.
If res.json() raises an error because it could not parse the JSON data, _serverError will not get a Response object, hence the reason for the instanceof check.
In this plunker, change url to ./data/data.junk to generate an error.
Users of either service should have code that can handle the error:
#Component({
selector: 'my-app',
template: '<div>{{data}}</div>
<div>{{errorMsg}}</div>`
})
export class AppComponent {
errorMsg: string;
constructor(private _myService: MyService ) {}
ngOnInit() {
this._myService.getData()
.subscribe(
data => this.data = data,
err => this.errorMsg = <any>err
);
}
}
There are several ways to do this. Both are very simple. Each of the examples works great. You can copy it into your project and test it.
The first method is preferable, the second is a bit outdated, but so far it works too.
1) Solution 1
// File - app.module.ts
import { BrowserModule } from '#angular/platform-browser';
import { NgModule } from '#angular/core';
import { HttpClientModule } from '#angular/common/http';
import { AppComponent } from './app.component';
import { ProductService } from './product.service';
import { ProductModule } from './product.module';
#NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule,
HttpClientModule
],
providers: [ProductService, ProductModule],
bootstrap: [AppComponent]
})
export class AppModule { }
// File - product.service.ts
import { Injectable } from '#angular/core';
import { HttpClient } from '#angular/common/http';
// Importing rxjs
import 'rxjs/Rx';
import { Observable } from 'rxjs/Rx';
import { catchError, tap } from 'rxjs/operators'; // Important! Be sure to connect operators
// There may be your any object. For example, we will have a product object
import { ProductModule } from './product.module';
#Injectable()
export class ProductService{
// Initialize the properties.
constructor(private http: HttpClient, private product: ProductModule){}
// If there are no errors, then the object will be returned with the product data.
// And if there are errors, we will get into catchError and catch them.
getProducts(): Observable<ProductModule[]>{
const url = 'YOUR URL HERE';
return this.http.get<ProductModule[]>(url).pipe(
tap((data: any) => {
console.log(data);
}),
catchError((err) => {
throw 'Error in source. Details: ' + err; // Use console.log(err) for detail
})
);
}
}
2) Solution 2. It is old way but still works.
// File - app.module.ts
import { BrowserModule } from '#angular/platform-browser';
import { NgModule } from '#angular/core';
import { HttpModule } from '#angular/http';
import { AppComponent } from './app.component';
import { ProductService } from './product.service';
import { ProductModule } from './product.module';
#NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule,
HttpModule
],
providers: [ProductService, ProductModule],
bootstrap: [AppComponent]
})
export class AppModule { }
// File - product.service.ts
import { Injectable } from '#angular/core';
import { Http, Response } from '#angular/http';
// Importing rxjs
import 'rxjs/Rx';
import { Observable } from 'rxjs/Rx';
#Injectable()
export class ProductService{
// Initialize the properties.
constructor(private http: Http){}
// If there are no errors, then the object will be returned with the product data.
// And if there are errors, we will to into catch section and catch error.
getProducts(){
const url = '';
return this.http.get(url).map(
(response: Response) => {
const data = response.json();
console.log(data);
return data;
}
).catch(
(error: Response) => {
console.log(error);
return Observable.throw(error);
}
);
}
}
The RxJS functions need to be specifically imported. An easy way to do this is to import all of its features with import * as Rx from "rxjs/Rx"
Then make sure to access the Observable class as Rx.Observable.
in the latest version of angular4 use
import { Observable } from 'rxjs/Rx'
it will import all the required things.

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