title: Optimaze Regex method (split alphanumeric words from a text line)
body: <p>I have issues with performance when using Regex.
  The methods I'm using is works as expected, but it takes long time to handle large text files.</p>
  
  <p>I need to take from each line of the file only words:
  "tjdj47***ss__s*47 djj ___ s_sd4 4"</p>
  
  <p>Should return list of words (any alpha or alphanumeric sequence that has more then 1 character)</p>
  
  <pre><code>tjdj47
  ss
  47
  djj
  sd4
  </code></pre>
  
  <p>I use Regex pattern</p>
  
  <pre><code> pattern = new Regex(
              @"([A-Za-z0-9]
              ([A-Za-z0-9])*
              [A-Za-z0-9])",
              RegexOptions.IgnorePatternWhitespace);
  </code></pre>
  
  <p>Method that filters and splits words</p>
  
  <pre><code>public List&lt;string&gt; SplitLineIntoWords(string lineText)
      {
          List&lt;string&gt; lineWords = new List&lt;string&gt;();
  
          foreach (Match m in pattern.Matches(lineText))
          {
              lineWords.Add(m.Groups[1].Value.ToLower());
          }
  
          return lineWords;
      }
  </code></pre>
  
  <p>How can I optimize method to execute faster? (Now, it takes up to 25 seconds to separate words from a file with size 350mb)</p>