Check out example codes for "ngForm". It will help you in understanding the concepts better.

Code Example 1

<form #f="ngForm" (ngSubmit)="onSubmit(f)" novalidate>
  <input name="first" ngModel required #first="ngModel">
  <input name="last" ngModel>
  <button>Submit</button>
</form>

<p>First name value: {{ first.value }}</p>
<p>First name valid: {{ first.valid }}</p>
<p>Form value: {{ f.value | json }}</p>
<p>Form valid: {{ f.valid }}</p>

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