title: C# string format flag or modifier to lowercase param
body: <p>Is it possible to specify some kind of flag or modifier on a string format param to make it lower case or upper case?</p>
  
  <p>Example of what I want:</p>
  
  <pre><code>String.Format("Hi {0:touppercase}, you have {1} {2:tolowercase}.", "John", 6, "Apples");
  </code></pre>
  
  <p>Wanted output:</p>
  
  <blockquote>
    <p>Hi JOHN, you have 6 apples.</p>
  </blockquote>
  
  <p>PS: Yes I know that I can change the case of the param before using it in the string format, but I don't want this.</p>