title: Ensure a base64 encoded string never includes a nonalphanumerical character
body: <p>Is there anyway to ensure that a base64 encoded string never includes a non-alphanumerical character?</p>
  
  <p>For example, if I have a long string that I encode, is there something I can prepend or append to it that will ensure that when encoded with base64 will only include letters and numbers in the encoded string? Something like this:</p>
  
  <p>String: <code>192.168.1.1</code></p>
  
  <p>Encoded: <code>MTkyLjE2OC4xLjE=</code> &lt;- I want to 'get rid' of the equal sign.</p>
  
  <p>I tried appending <code>}</code> at the end of the string (new string is now <code>192.168.1.1}</code>), and this worked (new encoded string: <code>MTkyLjE2OC4xLjF9</code>), but is there a method of ensuring every combination works?</p>
  
  <p>Is this possible?</p>