title: Using special characters as CASE keys in typoscript
body: <p>I'm trying to send a mail via the powermail extension to different receivers, depending on the value a user has selected in a form dropdown. This practice of <em>dynamic receivers</em> is described in the <a href="https://docs.typo3.org/typo3cms/extensions/powermail/5.5.0/ForAdministrators/BestPractice/DynamicReceiver/" rel="nofollow noreferrer">powermail documentation</a>. Basically:</p>
  
  <pre><code>receivers1.email = CASE
  receivers1.email {
  
      key.data = GP:tx_powermail_pi1|field|receiver
  
      1 = TEXT
      1.value = receivera@domain.org
  
      default = TEXT
      default.value = receiverb@domain.org
  }
  </code></pre>
  
  <p>Now I'm facing the following problem: my values for "receiver" are not numeric (as in the example), but text values from a dropdown. Some of them contain spaces, some of them contain umlauts (öäüß). If I try to add …</p>
  
  <pre><code>Not wörking = TEXT
  Not wörking.value = anotheremail@nowhere.org
  </code></pre>
  
  <p>Typo3 will complain and not update anything. (<em>Bad property!
  You must enter a property with characters a-z, A-Z and 0-9, no spaces!Nothing was updated!</em>)</p>
  
  <p>I tried simply 'escaping' the forbidden characters with a backslash, not working. Had an idea of converting the <code>key.data</code> via <code>stdWrap rawUrlEncode</code>, but did not work either. Google came up <a href="https://gist.github.com/dandjelkovic/2710837" rel="nofollow noreferrer">with this solution</a>, but I don't understand what's going on and could not use it successfully.</p>
  
  <p>How can I get around this? Thanks a lot for any kind of hint!</p>