דוגמא מלאה לעבודה עם DB

יצירת פרוייקט חדש

אם אנחנו מתחילים מהתחלה, ניצור פרוייקט חדש.

ng new crud-app --routing

נתקין את bootstrap כדי שיהיה קל יותר לעצב את הדפים.

npm install bootstrap

יצירת מודול לפוסטים וקומפוננטות מתאימות

ng generate module post --routing

ng generate component post/index
ng generate component post/view
ng generate component post/create
ng generate component post/edit

יצירת routes

src/app/post/post-routing.module.ts

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { IndexComponent } from './index/index.component';
import { ViewComponent } from './view/view.component';
import { CreateComponent } from './create/create.component';
import { EditComponent } from './edit/edit.component';

const routes: Routes = [
  { path: 'post', redirectTo: 'post/index', pathMatch: 'full'},
  { path: 'post/index', component: IndexComponent },
  { path: 'post/:postId/view', component: ViewComponent },
  { path: 'post/create', component: CreateComponent },
  { path: 'post/:postId/edit', component: EditComponent } 
];
  
@NgModule({
  imports: [RouterModule.forChild(routes)],
  exports: [RouterModule]
})
export class PostRoutingModule { }

יצירת מודל הפוסט

כדי לקבל את המידע בצורה של פוסטים ניצור interface שיחזיק את המידע הזה.

ng generate interface post/post

src/app/post/post.ts

export interface Post {
    id: number;
    title: string;
    body: string;
}

יצירת ה-service

ng generate service post/post

src/app/post/post.service.ts

import { Injectable } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http';
     
import {  Observable, throwError } from 'rxjs';
import { catchError } from 'rxjs/operators';
  
import { Post } from './post';
  
@Injectable({
  providedIn: 'root'
})
export class PostService {
  
  private apiURL = "https://jsonplaceholder.typicode.com";
    
  /*------------------------------------------
  Http Header Options
  --------------------------------------------*/
  httpOptions = {
    headers: new HttpHeaders({
      'Content-Type': 'application/json'
    })
  }
   
  /*------------------------------------------
  Created constructor
  --------------------------------------------*/
  constructor(private httpClient: HttpClient) { }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  getAll(): Observable<any> {
    return this.httpClient.get(this.apiURL + '/posts/')
    .pipe(
      catchError(this.errorHandler)
    )
  }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  create(post:Post): Observable<any> {
    return this.httpClient.post(this.apiURL + '/posts/', JSON.stringify(post), this.httpOptions)
    .pipe(
      catchError(this.errorHandler)
    )
  }  
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  find(id:number): Observable<any> {
    return this.httpClient.get(this.apiURL + '/posts/' + id)
    .pipe(
      catchError(this.errorHandler)
    )
  }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  update(id:number, post:Post): Observable<any> {
    return this.httpClient.put(this.apiURL + '/posts/' + id, JSON.stringify(post), this.httpOptions)
    .pipe( 
      catchError(this.errorHandler)
    )
  }
       
  /**
   * Write code on Method
   *
   * @return response()
   */
  delete(id:number){
    return this.httpClient.delete(this.apiURL + '/posts/' + id, this.httpOptions)
    .pipe(
      catchError(this.errorHandler)
    )
  }
      
  /** 
   * Write code on Method
   *
   * @return response()
   */
  errorHandler(error:any) {
    let errorMessage = '';
    if(error.error instanceof ErrorEvent) {
      errorMessage = error.error.message;
    } else {
      errorMessage = `Error Code: ${error.status}\nMessage: ${error.message}`;
    }
    return throwError(errorMessage);
 }
}

הוספת הלוגיקה והטמפלט של הקומפוננטה

בקובץ הראשי נקבל את כל רשימת הפוסטים. ברשימה נציג לכל פוסט את ה-ID, הכותרת והתוכן. לכל פוסט יהיו 3 כפתורים, צפייה בתוכן הפוסט, עריכה ומחיקה.

בקובץ ts נקבל את רשימת כל הפוסטים מה-service. בקובץ הזה גם נגדיר את פעולת ה-delete מכיוון שהפעולה הזאת לא שולחת לקומפוננטה אחרת לביצוע.

src/app/post/index/index.component.ts

import { Component, OnInit } from '@angular/core';
import { PostService } from '../post.service';
import { Post } from '../post';
      
@Component({
  selector: 'app-index',
  templateUrl: './index.component.html',
  styleUrls: ['./index.component.css']
})
export class IndexComponent implements OnInit {
      
  posts: Post[] = [];
    
  /*------------------------------------------
  Created constructor
  --------------------------------------------*/
  constructor(public postService: PostService) { }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  ngOnInit(): void {
    this.postService.getAll().subscribe((data: Post[])=>{
      this.posts = data;
      console.log(this.posts);
    })  
  }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  deletePost(id:number){
    this.postService.delete(id).subscribe(res => {
         this.posts = this.posts.filter(item => item.id !== id);
         console.log('Post deleted successfully!');
    })
  }

בקובץ ה-html נציג את הטבלה עם כל הפוסטים. בעמוד הזה יהיה גם כפתור ליצירת פוסט חדש.

src/app/post/index/index.component.html

<div class="container">
    <h1>All Posts</h1>
    
    <a href="#" routerLink="/post/create/" class="btn btn-success">Create New Post</a>
      
    <table class="table table-striped">
        <thead>
              <tr>
                <th>ID</th>
                <th>Title</th>
                <th>Body</th>
                <th width="250px">Action</th>
              </tr>
        </thead>
        <tbody>
              <tr *ngFor="let post of posts">
                <td>{{ post.id }}</td>
                <td>{{ post.title }}</td>
                <td>{{ post.body }}</td>
                <td>
                  <a href="#" [routerLink]="['/post/', post.id, 'view']" class="btn btn-info">View</a>
                  <a href="#" [routerLink]="['/post/', post.id, 'edit']" class="btn btn-primary">Edit</a>
                  <button type="button" (click)="deletePost(post.id)" class="btn btn-danger">Delete</button>
                </td>
              </tr>
        </tbody>
    </table>
 </div>

יצירת פוסט חדש

ניצור טופס לקבל את נתוני הפוסט ונשמור אותו.

src/app/post/create/create.component.ts

import { Component, OnInit } from '@angular/core';
import { PostService } from '../post.service';
import { Router } from '@angular/router';
import { FormGroup, FormControl, Validators} from '@angular/forms';
     
@Component({
  selector: 'app-create',
  templateUrl: './create.component.html',
  styleUrls: ['./create.component.css']
})
export class CreateComponent implements OnInit {
    
  form!: FormGroup;
    
  /*------------------------------------------
  Created constructor
  --------------------------------------------*/
  constructor(public postService: PostService, private router: Router) { }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  ngOnInit(): void {
    this.form = new FormGroup({
      title: new FormControl('', [Validators.required]),
      body: new FormControl('', Validators.required)
    });
  }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  get f(){
    return this.form.controls;
  }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  submit(){
    console.log(this.form.value);
    this.postService.create(this.form.value).subscribe((res:any) => {
         console.log('Post created successfully!');
         this.router.navigateByUrl('post/index');
    })
  }
}

הקובץ שמציג את הטופס.

src/app/post/create/create.component.html

<div class="container">
    <h1>Create New Post</h1>
  
    <a href="#" routerLink="/post/index" class="btn btn-primary">Back</a>
        
    <form [formGroup]="form" (ngSubmit)="submit()">
        <div class="form-group">
            <label for="title">Title:</label>
            <input 
                formControlName="title"
                id="title" 
                type="text" 
                class="form-control">
            <div *ngIf="f['title'].touched && f['title'].invalid" class="alert alert-danger">
                <div *ngIf="f['title'].errors && f['title'].errors['required']">Title is required.</div>
            </div>
        </div>
  
        <div class="form-group">
            <label for="body">Body</label>
            <textarea 
                formControlName="body"
                id="body" 
                type="text" 
                class="form-control">
            </textarea>
            <div *ngIf="f['body'].touched && f['body'].invalid" class="alert alert-danger">
                <div *ngIf="f['body'].errors && f['body'].errors['required']">Body is required.</div>
            </div>
        </div>
  
        <button class="btn btn-primary" type="submit" [disabled]="!form.valid">Submit</button>
    </form>
</div>

עריכת פוסט

בטופס העריכה נקבל את נתוני הפוסט הקיימים ונערוך אותם.

src/app/post/edit/edit.component.ts

import { Component, OnInit } from '@angular/core';
import { PostService } from '../post.service';
import { ActivatedRoute, Router } from '@angular/router';
import { Post } from '../post';
import { FormGroup, FormControl, Validators} from '@angular/forms';
     
@Component({
  selector: 'app-edit',
  templateUrl: './edit.component.html',
  styleUrls: ['./edit.component.css']
})
export class EditComponent implements OnInit {
      
  id!: number;
  post!: Post;
  form!: FormGroup;
    
  /*------------------------------------------
  Created constructor
  --------------------------------------------*/
  constructor(
    public postService: PostService,
    private route: ActivatedRoute,
    private router: Router
  ) { }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  ngOnInit(): void {
    this.id = this.route.snapshot.params['postId'];
    this.postService.find(this.id).subscribe((data: Post) => {
      this.post = data;
    }); 
      
    this.form = new FormGroup({
      title: new FormControl('', [Validators.required]),
      body: new FormControl('', Validators.required)
    });
  }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  get f(){
    return this.form.controls;
  }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  submit(){
    console.log(this.form.value);
    this.postService.update(this.id, this.form.value).subscribe((res:any) => {
         console.log('Post updated successfully!');
         this.router.navigateByUrl('post/index');
    })
  }
}

הצגת הטופס בקובץ ה-html.

products.component.html

<div class="container">
    <h1>Update Post</h1>
   
    <a href="#" routerLink="/post/index" class="btn btn-primary">Back</a>
          
    <form [formGroup]="form" (ngSubmit)="submit()">
    
        <div class="form-group">
            <label for="title">Title:</label>
            <input 
                formControlName="title"
                id="title" 
                type="text" 
                [(ngModel)]="post.title"
                class="form-control">
            <div *ngIf="f['title'].touched && f['title'].invalid" class="alert alert-danger">
                <div *ngIf="f['title'].errors && f['title'].errors['required']">Title is required.</div>
            </div>
        </div>
           
        <div class="form-group">
            <label for="body">Body</label>
            <textarea 
                formControlName="body"
                id="body" 
                type="text" 
                [(ngModel)]="post.body"
                class="form-control">
            </textarea>
            <div *ngIf="f['body'].touched && f['body'].invalid" class="alert alert-danger">
                <div *ngIf="f['body'].errors && f['body'].errors['required']">Body is required.</div>
            </div>
        </div>
         
        <button class="btn btn-primary" type="submit" [disabled]="!form.valid">Update</button>
    </form>
</div>

עמוד פרטי פוסט

כאן נקבל את הנתונים של הפוסט ונציג אותם.

src/app/post/view/view.component.ts

import { Component, OnInit } from '@angular/core';
import { PostService } from '../post.service';
import { ActivatedRoute, Router } from '@angular/router';
import { Post } from '../post';
    
@Component({
  selector: 'app-view',
  templateUrl: './view.component.html',
  styleUrls: ['./view.component.css']
})
export class ViewComponent implements OnInit {
  id!: number;
  post!: Post;
    
  /*------------------------------------------
  Created constructor
  --------------------------------------------*/
  constructor(
    public postService: PostService,
    private route: ActivatedRoute,
    private router: Router
   ) { }
    
  /**
   * Write code on Method
   *
   * @return response()
   */
  ngOnInit(): void {
    this.id = this.route.snapshot.params['postId'];
        
    this.postService.find(this.id).subscribe((data: Post) => {
      this.post = data;
    });
  }
}

נציג את הפוסט.

src/app/post/view/view.component.html

<div class="container">
    <h1>View Post</h1>
  
    <a href="#" routerLink="/post/index" class="btn btn-primary">Back</a>
   
    <div>
        <strong>ID:</strong>
        <p>{{ post.id }}</p>
    </div>
   
    <div>
        <strong>Title:</strong>
        <p>{{ post.title }}</p>
    </div>
   
    <div>
        <strong>Body:</strong>
        <p>{{ post.body }}</p>
    </div>
   
</div>

עדכונים אחרונים

בעמוד הראשי של הפרוייקט נמחק את כל התוכן ונשאיר רק את הניווט.

src/app/app.component.html

<router-outlet></router-outlet>

נוסיף את HttpClientModule לקובץ הראשי.

src/app/app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { HttpClientModule } from '@angular/common/http';
  
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
  
import { PostModule } from './post/post.module';
  
@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    PostModule,
    HttpClientModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

נייבא למודול הפוסט את כל הרכיבים שהשתמשנו בהם.

products.component.ts

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
  
import { PostRoutingModule } from './post-routing.module';
import { IndexComponent } from './index/index.component';
import { ViewComponent } from './view/view.component';
import { CreateComponent } from './create/create.component';
import { EditComponent } from './edit/edit.component';
  
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
  
@NgModule({
  declarations: [IndexComponent, ViewComponent, CreateComponent, EditComponent],
  imports: [
    CommonModule,
    PostRoutingModule,
    FormsModule,
    ReactiveFormsModule
  ]
})
export class PostModule { }

קצת ארוך, אבל מביא את כל הדברים בצורה ברורה ושלמה.