title: Stream StringBuilder to file
body: <p>I need to create a large text document.  I currently use <code>StringBuilder</code> to make the document and then call <code>File.WriteallText(filename,sb.ToString)</code>.  Unfortunately, this is now starting to throw out of memory exceptions. </p>
  
  <p>Is there a better way to stream a <code>StringBuilder</code> to file or is there some other technique I should be using?</p>