title: .NET Regex - "Not" Match
body: <p>I have a regular expression:</p>
  
  <pre><code>12345678|[0]{8}|[1]{8}|[2]{8}|[3]{8}|[4]{8}|[5]{8}|[6]{8}|[7]{8}|[8]{8}|[9]{8}
  </code></pre>
  
  <p>which matches if the string contains 12345679 or 11111111 or 22222222 ... or ... 999999999.</p>
  
  <p>How can I changed this to only match if NOT the above? (I am not able to just !IsMatch in the C# unfortunately)...EDIT because that is black box code to me and I am trying to set the regex in an existing config file</p>