title: Cannot translate date in current locale
body: <p>I'm trying to translate a <code>Date</code> in the current system language, this is my date: <code>2018/01/01</code>, I tried to achieve my goal in this way:</p>
  
  <pre><code>var date = DateTime.ParseExact("2018/01/01", "dddd MMMM yyyy", new CultureInfo("it-IT")).ToString();
  </code></pre>
  
  <p>unfortunately I get:</p>
  
  <blockquote>
    <p>System.ArgumentNullException</p>
  </blockquote>
  
  <p>The <code>InnerException</code> say:</p>
  
  <blockquote>
    <p>String not recognized as a valid DateTime value.</p>
  </blockquote>
  
  <p>I used <code>ParseExact</code> to avoid this error, what I did wrong? </p>