What is the best method to input 0 when ngModel is undefined in Angular version 6?

 <tr *ngFor="let item of capturaDiaria.inventarioList; let i = index">

  <td> <input type="number" class="form-control" [(ngModel)]="item.kg_blanca" name="blanca-{{i}}"> </td>

</tr>

Initially, if the user hasn't entered any data yet and the list is null, I want to display 0 in the input field.

Answer №1

Here are a couple of options:

  1. Set item.kg_blanca during the initialization process in ngOnInit()

or

  1. Develop a custom pipe that updates the value within the view

In my opinion, it's best to initialize the value at the beginning. If you utilize one-way data binding, using a getter could also be an effective solution.

Answer №2

To start, consider initializing it within the ngOnInit() lifecycle hook or even better...

[(ngModel)]="item.kg_blanca"

You could modify it to...

[(ngModel)]="item.kg_blanca !== null ? item.kg_blanca : '0"

This adjustment ensures that if the value is null, the input field will display 0 instead.

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