我期待检测我的路线变化AppComponent.
此后,我将检查全局用户令牌以查看他是否已登录.然后,如果用户未登录,我可以重定向用户.
我有点困惑如何获取key并value同时使用angular2对象的*ngFor用于遍历的对象.我知道在角度1.x中有一个类似的语法
ng-repeat="(key, value) in demo"
Run Code Online (Sandbox Code Playgroud)
但我不知道如何在angular2中做同样的事情.我尝试过类似的东西,没有成功:
<ul>
<li *ngFor='#key of demo'>{{key}}</li>
</ul>
demo = {
'key1': [{'key11':'value11'}, {'key12':'value12'}],
'key2': [{'key21':'value21'}, {'key22':'value22'}],
}
Run Code Online (Sandbox Code Playgroud)
以下是我的尝试:http ://plnkr.co/edit/mIj619FncOpfdwrR0KeG?p=preview
我怎样才能获得key1并key2动态使用*ngFor?经过广泛搜索后,我发现了使用管道的想法,但我不知道如何去做.是否有任何内置管道在angular2中做同样的事情?
我想在这个帖子中跟踪和更新最新的(并且希望是最简单的)方法来捆绑Angular(版本2,4,...)以便在实时Web服务器上进行生产.
请在答案中包含Angular版本,以便我们可以更好地跟踪它何时转移到更高版本.
我正在使用Angular 2(TypeScript).
我想为新的选择做点什么,但是我在onChange()中得到的东西总是最后选择.我怎样才能获得新的选择?
<select [(ngModel)]="selectedDevice" (change)="onChange($event)">
<option *ngFor="#i of devices">{{i}}</option>
</select>
onChange($event) {
console.log(this.selectedDevice);
// I want to do something here for new selectedDevice, but what I
// got here is always last selection, not the one I just select.
}
Run Code Online (Sandbox Code Playgroud) 我在Angular中遇到HTTP问题.
我只想要GET一个JSON列表并在视图中显示它.
import {Injectable} from "angular2/core";
import {Hall} from "./hall";
import {Http} from "angular2/http";
@Injectable()
export class HallService {
public http:Http;
public static PATH:string = 'app/backend/'
constructor(http:Http) {
this.http=http;
}
getHalls() {
return this.http.get(HallService.PATH + 'hall.json').map((res:Response) => res.json());
}
}
Run Code Online (Sandbox Code Playgroud)
在HallListComponent我getHalls从服务中调用方法:
export class HallListComponent implements OnInit {
public halls:Hall[];
public _selectedId:number;
constructor(private _router:Router,
private _routeParams:RouteParams,
private _service:HallService) {
this._selectedId = +_routeParams.get('id');
}
ngOnInit() {
this._service.getHalls().subscribe((halls:Hall[])=>{
this.halls=halls;
});
}
}
Run Code Online (Sandbox Code Playgroud)
但是,我有一个例外:
TypeError:this.http.get(...).map不是[null]中的函数 …
我正在使用EXCEPTION: No provider for Http!我的Angular应用程序.我究竟做错了什么?
import {Http, Headers} from 'angular2/http';
import {Injectable} from 'angular2/core'
@Component({
selector: 'greetings-ac-app2',
providers: [],
templateUrl: 'app/greetings-ac2.html',
directives: [NgFor, NgModel, NgIf, FORM_DIRECTIVES],
pipes: []
})
export class GreetingsAcApp2 {
private str:any;
constructor(http: Http) {
this.str = {str:'test'};
http.post('http://localhost:18937/account/registeruiduser/',
JSON.stringify(this.str),
{
headers: new Headers({
'Content-Type': 'application/json'
})
});
Run Code Online (Sandbox Code Playgroud) 谁能告诉我,如何使用jQuery的有角?
class MyComponent {
constructor() {
// how to query the DOM element from here?
}
}
Run Code Online (Sandbox Code Playgroud)
我知道有一些变通方法可以预先操作DOM元素的类或id,但是我希望有一种更简洁的方法.
我究竟做错了什么?
import {bootstrap, Component} from 'angular2/angular2'
@Component({
selector: 'conf-talks',
template: `<div *ngFor="let talk in talks">
{{talk.title}} by {{talk.speaker}}
<p>{{talk.description}}
</div>`
})
class ConfTalks {
talks = [ {title: 't1', speaker: 'Brian', description: 'talk 1'},
{title: 't2', speaker: 'Julie', description: 'talk 2'}];
}
@Component({
selector: 'my-app',
directives: [ConfTalks],
template: '<conf-talks></conf-talks>'
})
class App {}
bootstrap(App, [])
Run Code Online (Sandbox Code Playgroud)
错误是
EXCEPTION: Template parse errors:
Can't bind to 'ngForIn' since it isn't a known native property
("<div [ERROR ->]*ngFor="let talk in talks">
Run Code Online (Sandbox Code Playgroud) 更新到Angular 6.0.1后,我收到以下错误ng serve:
Could not find module "@angular-devkit/build-angular" from "/home/Projects/myProjectName".
Error: Could not find module "@angular-devkit/build-angular" from "/home/Projects/myProjectName".
at Object.resolve (/home/Projects/myProjectName/node_modules/@angular-devkit/core/node/resolve.js:141:11)
at Observable.rxjs_1.Observable [as _subscribe] (/home/Projects/myProjectName/node_modules/@angular-devkit/architect/src/architect.js:132:40)
Run Code Online (Sandbox Code Playgroud)
ng update说一切都井然有序.删除node_modules文件夹和全新npm install安装也没有帮助.
我的项目基于[ng2-admin(Angular4版本)].(https://github.com/akveo/ngx-admin)这是我的package.json dependecies:
"dependencies": {
"@angular/animations": "^6.0.1",
"@angular/common": "^6.0.1",
"@angular/compiler": "^6.0.1",
"@angular/core": "^6.0.1",
"@angular/forms": "^6.0.1",
"@angular/http": "^6.0.1",
"@angular/platform-browser": "^6.0.1",
"@angular/platform-browser-dynamic": "^6.0.1",
"@angular/platform-server": "^6.0.1",
"@angular/router": "^6.0.1",
"@ng-bootstrap/ng-bootstrap": "1.0.0-alpha.26",
"@ngx-translate/core": "^10.0.1",
"@ngx-translate/http-loader": "^3.0.1",
"amcharts3": "github:amcharts/amcharts3",
"ammap3": "github:amcharts/ammap3",
"angular-table": "^1.0.4",
"angular2-csv": "^0.2.5",
"angular2-datatable": "0.6.0",
"animate.css": "3.5.2",
"bootstrap": "4.0.0-alpha.6", …Run Code Online (Sandbox Code Playgroud) angular ×10
angular-cli ×2
typescript ×2
angular6 ×1
jquery ×1
object ×1
rxjs ×1
systemjs ×1
webpack ×1