Error: Select dropdown placeholder malfunctioning

Even after trying numerous solutions from various forums, I am unable to make the placeholder display in my code. Maybe a fresh perspective can help spot what I might be missing. view image here

I have experimented with using "" as the value, as well as disable and hidden attributes, and even tried not creating a variable and simply typing the phrase. But nothing seems to work.

Here is the current output: view image here

Despite trying some top search results, none of them seem to be effective.

*****update https://i.sstatic.net/bRHeH.png

Out of the five attempts, only 3 are successful. The issue may lie with the array I'm using *ngFor... I vaguely remember reading something about that. For the other two attempts, the code is identical to the first successful one but for some reason, the placeholder refuses to work.

angulartypescript

Answer №1

One clever way to create an option that appears as a label on initial load is to set its value to undefined and disable it. This allows the user to select the correct value after loading!

<form #f="ngForm" (ngSubmit)="save()">
  <select
    [(ngModel)]="selected"
    name="valueCheck"
    (change)="valueChange($event)"
  >
    <option [ngValue]="undefined" disabled>Choose...</option>
    <option
      *ngFor="let obj of stud"
      [ngValue]="obj.rnNo"
      [selected]="obj.rnNo == selected"
    >
      {{ obj.name }}
    </option>
  </select>
  <button type="submit">submit</button>
  <button (click)="clear()">clearValue</button>
</form>
<h3>{{ selected }}</h3>

ts

...
export class AppComponent {
    selected!: number;
...

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