title: Converting random letters within a string to Upper/Lower Case
body: <p>I have a bot for my discord that I am adding a command to post one of those spongebob memes that you may have seen on twitter recently. I basically have to convert a string that the user enters, for example <code>This is the string they would enter</code> and it would convert it to something like this <code>THis iS ThE sTRinG thEy WOulD EnTEr</code></p>
  
  <p>I need to basically randomly set each character in that string to and uppercase or a lowercase. 
  Here is what I have so for, it prints out the original string and not the converted one.</p>
  
  <pre><code>commands.CreateCommand("spongememe").Parameter("message", ParameterType.Multiple).Do(async (e) =&gt;
          {
              string message = "";
              for (int i = 0; i &lt; e.Args.Length; i++)
              {
                  message += e.Args[i].ToString() + " ";
              }
  
              char[] array = message.ToCharArray();
  
              for(int i = 0; i &lt; array.Length; i++)
              {
                  if (rnd.Next(0, 2) == 1)
                      Char.ToUpper(array[i]);
                  else
                  {
                      Char.ToLower(array[i]);
                  }
              }
  
              string newMessage = String.Join("", array);
  
              await e.Channel.SendMessage(newMessage);
  
          });
  </code></pre>
  
  <p>Any help on how to randomly select which characters are set to upper and lower case would be appreciated.</p>