title: C# regex.split method is adding empty string before parenthesis
body: <p>I have some code that tokenizes a equation input into a string array:</p>
  
  <pre><code>string infix = "( 5 + 2 ) * 3 + 4";
  string[] tokens = tokenizer(infix, @"([\+\-\*\(\)\^\\])");
  foreach (string s in tokens)
  {
     Console.WriteLine(s);
  }
  </code></pre>
  
  <p>Now here is the tokenizer function:</p>
  
  <pre><code>public string[] tokenizer(string input, string splitExp)
          {
              string noWSpaceInput = Regex.Replace(input, @"\s", "");
              Console.WriteLine(noWSpaceInput);
              Regex RE = new Regex(splitExp);
              return (RE.Split(noWSpaceInput));
          }
  </code></pre>
  
  <p>When I run this, I get all characters split, but there is an empty string inserted before the parenthesis chracters...how do I remove this?</p>
  
  <p>//empty string here</p>
  
  <p>(</p>
  
  <p>5</p>
  
  <p>+</p>
  
  <p>2</p>
  
  <p>//empty string here</p>
  
  <p>)</p>
  
  <p>*</p>
  
  <p>3</p>
  
  <p>+</p>
  
  <p>4</p>