MiHawk MiHawk - 3 days ago 9
TypeScript Question

Property 'toPromise' does not exist on type 'Observable<Response>'



import { Headers, Http } from '@angular/http';
import 'rxjs/add/operator/toPromise';

@Injectable()
export class PublisherService{

private publishersUrl = 'app/publisher';

constructor(private http: Http) { }

getPublishers(): Promise<Publisher[]>{
return this.http.get(this.publishersUrl)
.toPromise()
.then(response => response.json().data)
.catch(this.handleError);
}
}

package.json is as follows

{
"name": "angular2-quickstart",
"version": "1.0.0",
"scripts": {
"start": "tsc && concurrently \"npm run tsc:w\" \"npm run lite\" ",
"lite": "lite-server",
"postinstall": "typings install",
"tsc": "tsc",
"tsc:w": "tsc -w",
"typings": "typings"
},
"license": "ISC",
"dependencies": {
"@angular/common": "2.0.0-rc.2",
"@angular/compiler": "2.0.0-rc.2",
"@angular/core": "2.0.0-rc.2",
"@angular/http": "2.0.0-rc.2",
"@angular/platform-browser": "2.0.0-rc.2",
"@angular/platform-browser-dynamic": "2.0.0-rc.2",
"@angular/router": "2.0.0-rc.2",
"@angular/router-deprecated": "2.0.0-rc.2",
"@angular/upgrade": "2.0.0-rc.2",
"angular2-in-memory-web-api": "0.0.12",
"bootstrap": "^3.3.6",
"core-js": "^2.4.0",
"reflect-metadata": "^0.1.3",
"rxjs": "5.0.0-beta.6",
"systemjs": "0.19.27",
"zone.js": "^0.6.12"
},
"devDependencies": {
"concurrently": "^2.0.0",
"lite-server": "^2.2.0",
"typescript": "^1.8.10",
"typings": "^1.0.4"
}
}

<!-- begin snippet: js hide: false console: true babel: false -->







System js below

(function(global) {

var map = {
'app': 'app', // 'dist',
'@angular': 'node_modules/@angular',
'angular2-in-memory-web-api': 'node_modules/angular2-in-memory-web-api',
'rxjs': 'node_modules/rxjs'
};

var packages = {
'app': { main: 'main.js', defaultExtension: 'js' },
'rxjs': { defaultExtension: 'js' },
'angular2-in-memory-web-api': { main: 'index.js', defaultExtension: 'js' },
};
var ngPackageNames = [
'common',
'compiler',
'core',
'http',
'platform-browser',
'platform-browser-dynamic',
'router',
'router-deprecated',
'upgrade',
];

function packIndex(pkgName) {
packages['@angular/'+pkgName] = { main: 'index.js', defaultExtension: 'js' };
}

function packUmd(pkgName) {
packages['@angular/'+pkgName] = { main: '/bundles/' + pkgName + '.umd.js', defaultExtension: 'js' };
}

var setPackageConfig = System.packageWithIndex ? packIndex : packUmd;

ngPackageNames.forEach(setPackageConfig);
var config = {
map: map,
packages: packages
};
System.config(config);
})(this);







I am getting error Property 'toPromise' does not exist on type 'Observable'.any

Answer

You need to add the operator like this:

import 'rxjs/add/operator/toPromise';

This is needed for every rxjs operator you want to use.

Comments