title: RegEx with counting digits and allow special chars
body: <p>I've done some searching but cant find the right regex.</p>
  
  <p>i would like a regex for a text that only contains digits, whitespaces and plus signs.
  like: [0-9 +]</p>
  
  <p>But with a min/max limit for only the digits in that text.</p>
  
  <p>My suggestions ended up with something like this:</p>
  
  <pre><code>    ^[0-9 \+](?=(.*[0-9]){5,8})$
  </code></pre>
  
  <p>Should be OK:</p>
  
  <ul>
  <li>"123 456 7"  </li>
  <li>"12345"</li>
  <li>"+ 123 456 78"</li>
  </ul>
  
  <p>Should not be ok:</p>
  
  <ul>
  <li>"123456789" </li>
  <li>"+ 124 578a"  </li>
  <li>"+123456789"</li>
  </ul>
  
  <p>Anyone got a solution that might do the trick?</p>
  
  <p>Edit:</p>
  
  <p>I can see that i was to short on my explanation what i'm aiming for. </p>
  
  <p>My regex conditions should be: </p>
  
  <ul>
  <li>Must include between 5-8 digits </li>
  <li>Allow whitespaces and plus signs</li>
  </ul>