title: Good form validation in Angular 5
body: <p>Good morning everyone,</p>
  
  <p>I want to achieve the following behaviour with an ng5 form:</p>
  
  <ul>
  <li>When customer touched a form control and the input is invalid, then the form control should be marked as invalid</li>
  <li>When the customer touches no form control and then hits "submit" all form controls should be validated</li>
  <li>The submit button should be always active. I don´t really like the "disable submit button until everything is ok" theory cause it doesn´t tell the user what´s wrong with his inputs</li>
  </ul>
  
  <p>So validation of controls onchange works fine, but what I´m missing is a "form.validate()" method. Also the new "updateOn" feature doesn´t solve this issue, cause then it´s an either-or solution, not a combination of submit- and change validation.</p>
  
  <p>The only solution I found was to develop a validate() method myself which iterates over all controls of a form.</p>
  
  <p>Maybe somebody has an idea for me? :)</p>
  
  <p>Thanks &amp; best,
  Michael</p>