title: Validator minLength FormGroup Reactive form
body: <p>I am trying to validate a <code>minLength</code> but it does not recognize it, for that I am using a function. I have also tried it directly in the template but I do not get any results.</p>
  
  <p>myComponent.html</p>
  
  <pre><code>&lt;mat-form-field&gt;
      &lt;input matInput placeholder="Ingresa tu celular" type="number" formControlName="celular"&gt;
      &lt;mat-error *ngIf="forma.controls['celular'].invalid"&gt;{{ errorCelular() }}&lt;/mat-error&gt;
    &lt;/mat-form-field&gt;
  </code></pre>
  
  <p>myComponent.ts</p>
  
  <pre><code>celular: [ '', [Validators.required, Validators.minLength(9)] ],
  
  
  errorCelular() {
  return this.forma.controls.celular.hasError('required') ? 'El celular es necesario.' :
  this.forma.controls.celular.hasError('minlength')? 'Mínimo 9 caracteres': '';
  }
  </code></pre>