staticvoid Main(string[] args)
{
int len ="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ".Length -1;
char[] code ="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray(0, len +1);
int i =new Random(DateTime.Now.Millisecond).Next(0, len);
Console.Write(code[i]);
i =new Random(DateTime.Now.Millisecond*0xFFFF).Next(0, len);
Console.Write(code[i]);
i =new Random(DateTime.Now.Millisecond*0xAAAA).Next(0, len);
Console.Write(code[i]);
i =new Random(DateTime.Now.Millisecond*0xCCCC).Next(0, len);
Console.Write(code[i]);
}