title: Angular7 reactive form material time input validation
body: <p>I have an angular 7 reactive form, input field in this form is to let user see and modify time and then using Save() save it back to our db, the problem is that user can enter any none sense numbers in this field which dose not make sense in terms of Time.(like hours should be 1-24, Minutes 1-60)
  My question is how can I validate what user entered into time field and if its valid then let Save btn be active?</p>
  
  <p>Note: Based on my testing even though its none sense time entry but while trying to save its not saving to db and its probably sql not letting that happen.</p>
  
  <p>I googled but i could not find anything, also angular has only email Validators which u can put while defining form.</p>
  
  <p>this is my form defination</p>
  
  <pre><code>timeForm: FormGroup = new FormGroup({
      Id: new FormControl(''),
      Time: new FormControl(''),
    });
  </code></pre>
  
  <p>and this is my HTML side</p>
  
  <pre><code>&lt;form style="background-color: aliceblue;" [formGroup]="service.timeForm"&gt;
    &lt;mat-grid-list cols="1" rowHeight="120px"&gt;
      &lt;mat-grid-tile&gt;
        &lt;div class="form-controles-container"&gt;
          &lt;input type="hidden" formControlName="Id" /&gt;
          &lt;mat-form-field&gt;
            &lt;input formControlName="Time" matInput placeholder="Time" /&gt;
          &lt;/mat-form-field&gt;
          &lt;div class="button-row"&gt;
            &lt;button mat-raised-button color="primary" type="submit" (click)="Save()"&gt;Save&lt;/button&gt;
            &lt;button mat-raised-button color="warn" (click)="Cancel()"&gt;Cancel&lt;/button&gt;
          &lt;/div&gt;
        &lt;/div&gt;
      &lt;/mat-grid-tile&gt;
    &lt;/mat-grid-list&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>I need some sort of validation when user punch in any input which dose not make sense in Time my Save btn should not be activated.</p>
  
  <p>I appreciate your help and guideline.</p>