angular6

问题 I'm trying to sort a MatTable with MatSort of angular material but the problem is I can sort only two columns of my MatTable but what I want is to sorting all my columns and I don't understand why it doesn't work... I can click on the arrow like when I want to sort data of my table but nothing happens except with column multiple and occupation which are sorting well. Here is my code (I'm well importing MatSortModule into my app.module.ts ): csr.component.ts import {AfterViewInit, Component,

问题 I have the following piece of code which works correctly. public createData(data:Data):Observable<any>{ console.log('contacting server at '+this.API_URL +this.NEW_DATA_URL +" with data "+data+ " with httpOptions "+httpOptions.withCredentials + ","+httpOptions.headers ); let newData = new Data(data) let body = JSON.stringify(newQuestion); //I WANT TO MOVE THE CODE BELOW INTO A FUNCTION BUT AM GETTING COMPILATION ERROR this.loaderService.show(); return this.http.post(this.NEW_QUESTION_URL,body

问题 Cannot read property 'length' of undefined TypeError: Cannot read property 'length' of undefined at levenshtein (F:\Learnings\AngularHandsOn\Angular6\angular6Handson\node_modules\@angular\cli\models\command-runner.js:58:23) at listAllCommandNames.sort (F:\Learnings\AngularHandsOn\Angular6\angular6Handson\node_modules\@angular\cli\models\command-runner.js:69:43) at Array.sort (native) at Object. (F:\Learnings\AngularHandsOn\Angular6\angular6Handson\node_modules\@angular\cli\models\command

问题 I use the beta of ionic 4 for the first time. I try to disable the menu on a login page, but i have some trouble. I've created the app with ionic-cli and the sidemenu template, then I generated a login page. I removed the <ion-split-pane> from the app.component.html I modified the app-routing.module.ts to redirect to my login screen. In my login file, I tried to put an ngOnInit event to disable the menu on this specific page import { Component, OnInit, AfterContentInit, AfterViewInit

问题 I am opening a Modal in two different ways Stackblitz Example: Calling a method in a component which calls the Modal Service: <button (click)="openModal()">Open Modal</button> export class AppComponent { constructor(private modalService: ModalService) { } openModal() { this.modalService.open(HelloComponent); } } The Modal service creates the component dynamically. Using a directive that then calls the ModalService: <button [modal]="'HelloComponent'">Open Modal</button> @Directive({ selector:

问题 I'm trying to display the data on the front end but i get the above error. How to resolve this? service.ts rec_source(){ var headers = new HttpHeaders().set('Authorization', 'Token ' + localStorage.getItem('usertoken')); headers.append('Accept', 'application/json'); var options = { headers: headers }; return this.httpClient.get('api/recruit/fetch_recruitment_details',options) } component.ts sources:any = []; constructor(private Authentication:AuthService) { } ngOnInit() { this.Authentication

问题 In my app I have two main parts: Authorization - login and registration pages Panel - basic app pages In my app.component.html I have router outlet for navigation to Authorization and Panel components. However in the mentioned components I have another router outlets for navigation between cards (subcomponents). I tried to do routing separetly for each module, but it doesnt work. When I go to path eg. "/authorization/login" I got error that such url doesnt exists. Here is my app-routing

问题 I'm building a crud operation and was able to do the create operation. Now I'm trying to edit and delete them. I tried getting individual data through service but failed. It would be nice if anyone could help me with this. service.ts // Fetch Role Data getRoleData(){ var headers = new HttpHeaders().set('Authorization', 'Token ' + localStorage.getItem('usertoken')); var options_role = { headers: headers }; return this.httpClient.get('api/auth/role/', options_role); } // Add Data sendRole(data)

问题 I want to be able to pass components and other html into other components in this way: <app-container-component> <h3>All these items should be displayed in parent component</h3> <app-another-component></app-another-component> </app-container-component> How can I read inner items of container-component and render them inside component template? 回答1: You can use the concept of "@Input","@Output-EventEmitter".By using these properties you can pass data from parent component to child component

问题 I'm trying to use map operator from RxJS but it throws an error saying Property 'map' does not exist on type 'Observable'. Here is the code import { Injectable } from "@angular/core"; import { Http } from "@angular/http"; import "rxjs/add/operator/map"; @Injectable() export class DataService { constructor(public http: Http) {} getData() { return this.http .get("https://jsonplaceholder.typicode.com/users") .map(res => res.json()); } } 回答1: For first Http is deprecated in higher versions than