title: Ignore Regex escape sequences C#
body: <p>I'm having trouble telling Regex to ignore any escape sequences.</p>
  
  <p>Here is some example code:</p>
  
  <pre><code>string input = "?";
  foreach (Match m in Regex.Matches(input, "?"))
        {
           ...
        }
  </code></pre>
  
  <p>But when it is executed, it throws the following error:
  parsing "?" - Quantifier {x,y} following nothing.</p>
  
  <p>I just want the "?" to be handled as a string.</p>
  
  <p>Thanks.</p>
  
  <p>EDIT:
  I have also tried:</p>
  
  <pre><code>foreach (Match m in Regex.Matches(input, "\?"))
                  {
  ...
                  }
  </code></pre>
  
  <p>Which tells me that is is not recognized as a valid escape sequence.</p>
  
  <p>I've also tried:</p>
  
  <pre><code>foreach (Match m in Regex.Matches(input, "\x3f"))
                  {
  ...
                  }
  </code></pre>