Angular 5 Material: Dropdown (select) Required Validation Is Not Working


Answer :

Based on the excellent answer of (from zero to hero), I want to clarify 2 points mentioned in comments:

1- You have to use ngModel not value

2- You have to give the control a name

Full credit goes to him, I wanted to clarify this to any newcomer like me as it took me 2 hours to find out why it doesn't work


You added required to the select's option, not the select. Do it like:

<mat-form-field>   <mat-select placeholder="Favorite food" name="select" [(ngModel)]="select" required>     <mat-option *ngFor="let food of foods" [value]="food.value" >       {{ food.viewValue }}     </mat-option>   </mat-select> </mat-form-field>

DEMO


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