Generate random characters between A-Z with C#
Random rnd = new Random(DateTime.Now.Millisecond);
string letter = char.ConvertFromUtf32(rnd.Next(65, 90));
Random rnd Is a pseudorandom number generator
rnd.Next(65, 90) Returns a random number within the specified range
char.ConvertFromUtf32(rnd.Next(65, 90)); Converts a decimal number to its equivalent ASCII character