tying the [(ngModel)] to a value that is not defined

Currently facing an issue with the [(ngModel)] below as I am not receiving any values from the backend:

<input type="number" 
     [(ngModel)]="list.test[0]">

The error arises due to the absence of values in the test array from the backend, resulting in a property 0 of undefined error.

I attempted using [(ngModel)]="list?.test[0]" but it did not resolve the issue either.

Answer №1

The two-way binding in Angular does not currently support the safe navigation operator ?.

If you need this functionality, there is an ongoing feature request for it that you can track here: https://github.com/angular/angular/issues/7697

In the meantime, you can use a workaround like this:

[(ngModel)]="list.test && list.test[0]"

For example, if you have 3 input fields, your code should look something like this:

<form>
<input type="number" name="item1" [(ngModel)]="list.test && list.test[0]">
<input type="number" name="item2" [(ngModel)]="list.test && list.test[1]">
<input type="number" name="item3" [(ngModel)]="list.test && list.test[2]">
</form>

Make sure to provide each input field with a unique name attribute.

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