title: Expression.Call usage
body: <p>I have tried to convert the string to <code>ToLower</code> case using the below Expression call.</p>
  
  <pre><code>var tolowerMethod = typeof(string).GetMethods().Where(m =&gt; m.Name == "ToString").FirstOrDefault(); 
  var toLowerMethodCall = Expression.Call(memExp,tolowerMethod,new Expression[0]);
  </code></pre>
  
  <p>I am facing some issue to create an Expression call to format a value like: <code>"05/12/2012 12:00:00"</code> to <code>{0:MM/dd/yyyy}</code>. </p>