javascript - 访问 Angular Material 表中的输入字段

Question

几天来我一直在尝试从 Angular Material 表中的输入字段获取数据。

我基本上是用来自 API 的值填充一个表，但是每当我们没有得到任何日期时，在我的情况下，类(class)没有安排的日期集，我插入一个文本框，其中的值应该显示，以便用户可以为该特定类(class)设置日期。

像这样: 注意:对审查感到抱歉，必须删除与工作相关的名称。

这是我的 html 代码:

<mat-card>
    <form  #traineeForm="ngForm">
      <mat-form-field>
        <input  readonly matInput type="text" name="name" [ngModel] = "trainee.name"  #name="ngModel">
      </mat-form-field>
      <mat-form-field>
        <input readonly matInput email type="text"  name="email" [ngModel] = "trainee.email" #email="ngModel">
      </mat-form-field>
      <mat-form-field>
        <input readonly matInput type="text"  name="type" [ngModel] = "trainee.type" #type="ngModel">
      </mat-form-field>
      <button mat-raised-button color ="primary" type ="submit">Edit</button>
      <button mat-raised-button color ="warn" type ="submit" (click)="onDelete(trainee.id)">Delete</button>
    </form>
  </mat-card>
<br>
  <mat-card>
    
      <table mat-table [dataSource]="courses" class="mat-elevation-z8">
      
      <ng-container matColumnDef="courseOrderID">
        <th mat-header-cell *matHeaderCellDef>Course Order ID</th>
        <td mat-cell *matCellDef="let element"> {{element.courseOrderID}}</td>
      </ng-container>
      
       <ng-container matColumnDef="title">
          <th mat-header-cell *matHeaderCellDef>Course Title </th>
          <td mat-cell *matCellDef="let element"> {{element.title}}</td>
      </ng-container>
      <ng-container matColumnDef="description">
          <th mat-header-cell *matHeaderCellDef>Course Description </th>
          <td mat-cell *matCellDef="let element"> {{element.description}}</td>
       </ng-container>
      <ng-container matColumnDef="duration">
          <th mat-header-cell *matHeaderCellDef>Duration </th>
          <td mat-cell *matCellDef="let element"> {{element.duration}}</td>
      </ng-container>
      <ng-container matColumnDef="scheduledDate">
        <th mat-header-cell *matHeaderCellDef>Scheduled Date </th>
      <td mat-cell *matCellDef="let element">
         <mat-form-field>
              <input matInput [matDatepicker]="picker" placeholder="Choose a date">
              <mat-datepicker-toggle matSuffix [for]="picker"></mat-datepicker-toggle>
              <mat-datepicker #picker></mat-datepicker>
          </mat-form-field>
         {{element.scheduledDate}}</td>
      </ng-container>
      <ng-container matColumnDef="trainer">
          <th mat-header-cell *matHeaderCellDef>Trainer </th>
          <td mat-cell *matCellDef="let element">
              <mat-form-field><input matInput color="warn" *ngIf="!element.trainer"></mat-form-field> {{element.trainer}}</td>
      </ng-container>
      <ng-container matColumnDef="save">
          <th mat-header-cell *matHeaderCellDef></th>
          <td mat-cell *matCellDef="let element">
              <button mat-raised-button color ="primary" type ="submit" (click)="onSaveAssignment(trainee, element, picker)">Save</button></td>
      </ng-container>
      <tr mat-header-row *matHeaderRowDef="coursesdisplayColumns">
      </tr>
      <tr mat-row *matRowDef="let courses; columns: coursesdisplayColumns"></tr>
      </table>
      <br>
 
      </mat-card>

这是我的 TypeScript 代码:

import { Trainee } from '../trainees.model';
import { Component, OnInit, OnDestroy } from '@angular/core';
import { Subscription } from 'rxjs';
import { TraineesService } from '../../trainees.service';
import { ActivatedRoute, ParamMap } from '@angular/router';
import { Course } from '../../courses/courses.model';
import { CoursesService } from '../../courses.service';
import { Assignment } from '../../assignments/assignments.model';
import { NgForm } from '@angular/forms';

@Component({
  selector: 'app-trainee-details',
  templateUrl: './trainee-details.component.html',
  styleUrls: ['./trainee-details.component.css']
})


export class TraineeDetailsComponent implements OnInit, OnDestroy {
  
  private traineeId: string;
  trainee: Trainee;
  assignment: Assignment;
  courses: Course[] = [];
  coursesdisplayColumns = ['courseOrderID', 'title','description','duration','scheduledDate','trainer','save'];
  
  constructor(public traineeService: TraineesService, public route: ActivatedRoute, public coursesService: CoursesService){}

  ngOnInit() {
    this.route.paramMap.subscribe((paramMap: ParamMap) => {
      if(paramMap.has('traineeId')){
        this.traineeId = paramMap.get('traineeId');
        this.trainee = this.traineeService.getTrainee(this.traineeId);
      }
    });
    this.coursesService.getCoursesByJob(this.trainee.job);
    this.coursesService.getCoursesUpdateListener().subscribe((courses: Course[]) =>{
      this.courses = courses;
    });
  }

  onDelete(traineeId: string)
  {
    this.traineeService.deleteTrainee(traineeId);
  }
  onSaveAssignment(trainee: Trainee, selectedCourse: Course, dateForm: Date){
  
    console.log(trainee.id);
    console.log(selectedCourse.description);
    console.log(dateForm);
  }
  ngOnDestroy() {

  }
}

当我调用 onSaveAssignment() 时，受训者 ID 和类(class) ID 正确地记录在控制台中，因为它们是在 typescript 中定义的，但我不知道我应该如何在界面中选择那个日期，我尝试使用 ng -model 但它不起作用，我必须为每个输入定义一个表单，但仍然不起作用。

当按下“保存”按钮时，有没有办法从每一行的输入中获取该值？

或者，如果我为所有按钮放置 1 个按钮，是否有任何方法可以对界面中的每个输入值执行 foreach？

Answer 1

您可以通过使用索引作为属性创建包含所有值的对象来使用 ngModel 获取值。

在你的组件中，放置一个对象:

public myDates : any = {};

然后将 ngModel 与输入日期的索引一起使用:

<ng-container matColumnDef="scheduledDate">
  <th mat-header-cell *matHeaderCellDef>Scheduled Date </th>
  <td mat-cell *matCellDef="let element; let i = index">
    <mat-form-field>
      <input matInput [(ngModel)]="myDates[i]" [matDatepicker]="picker" placeholder="Choose a date">
      <mat-datepicker-toggle matSuffix [for]="picker"></mat-datepicker-toggle>
      <mat-datepicker #picker></mat-datepicker>
    </mat-form-field>
  </td>
</ng-container>

对于每一行，它将向对象 myDates 添加一个属性。使用索引允许保证唯一性。您的对象将如下所示:{1: date1, 2: date2 ...}。

然后就可以通过知道行的索引来获取值了。点击按钮可以直接获取:

<ng-container matColumnDef="save">
  <th mat-header-cell *matHeaderCellDef></th>
  <td mat-cell *matCellDef="let element; let i = index">
    <button mat-raised-button color ="primary" type ="submit" (click)="onSaveAssignment(trainee, element, myDates[i])">Save</button>
  </td>
</ng-container>