No. The command line arguments are strings, and they are (effectively) arrays of characters. You cannot convert a string to a character any more than you can convert a shelf of books into a single novel. And your code doesn't even try - it deoesn't even use the arguments themselves!
Depending on what you want to do with the command line argument, you could compare it directly as a string:
foreach(string cmd in Environment.GetCommandLineArgs())
case "Command1": ProcessCommand1(); break;
case "Command2": ProcessCommand2(); break;