How do I implement nested form groups in Angular CLI with validation?

How do I implement nested form groups in Angular CLI with validation?

To implement nested form groups in Angular, you can use the FormGroup and FormArray classes from @angular/forms. First, create a FormGroup for your main form, and then create nested FormGroups for the sub-forms.

Can you show me a code example?

Sure! Here's a simple example:

import { FormGroup, FormBuilder, Validators } from '@angular/forms';

this.myForm = this.fb.group({
  user: this.fb.group({
    name: ['', Validators.required],
    email: ['', [Validators.required, Validators.email]]
  }),
  address: this.fb.group({
    street: ['', Validators.required],
    city: ['', Validators.required]
  })
});

How do I add validation messages for the nested fields?

You can display validation messages by checking the validity of each control. For example:

<div *ngIf="myForm.get('user.name').invalid && myForm.get('user.name').touched">
  Name is required.
</div>