title: C# regular expression excluding tags with random element names
body: <p>I'm trying to get the opposite of this expression and it's giving me some trouble.</p>
  
  <p>Ex.</p>
  
  <pre><code>expression: (?&lt;={{)(.*?)(?=}})
  string: this is a question with a textbox {{textbox}} ok
  results: textbox
  </code></pre>
  
  <p>Looking for something like</p>
  
  <pre><code>expression: !(?&lt;={{)(.*?)(?=}})
  string:this is a question with a textbox {{textbox}} ok 
  results: this is a question with a textbox ok
  </code></pre>
  
  <p>Also, I should note that whats in the {{}}'s is not always textbox and will be random alphabetic characters.</p>