title: What is the regular expression to allow uppercase/lowercase (alphabetical characters), periods, spaces and dashes only?
body: <p>I am having problems creating a regex validator that checks to make sure the input has uppercase or lowercase alphabetical characters, spaces, periods, underscores, and dashes only.  Couldn't find this example online via searches. For example:</p>
  
  <p>These are ok:</p>
  
  <pre><code>Dr. Marshall
  sam smith
  .george con-stanza .great
  peter.
  josh_stinson
  smith _.gorne
  </code></pre>
  
  <p>Anything containing other characters is not okay. That is numbers, or any other symbols.</p>