title: How do I write a Perl regular expression that will match a string with only these characters?
body: <p>I am pretty new to regular expressions. I want to write a regular expression which validates whether the given string has only certain characters. If the string has any other characters than these it should not be matched.</p>
  
  <p>The characters I want are:</p>
  
  <pre><code> &amp; ' : , / - ( ) . # " ; A-Z a-z 0-9
  </code></pre>