Need Keygen. And checking keys in the program.

can you advise code example?

you can some simple.

Answer 1, Authority 100%

I so threw the code that interests you:

How to protect the application from execution of arguments?

But because The question sounds quite different, you do not need to consider it a duplicate.
Therefore, I just duplicate the code here:

class program
{
  Static Void Main (String [] Args)
  {
    var Mac = getMacadress ();
    Console.Writeline (GetNumbersFromMac (Mac) + GetMirrowcharsfrommac (Mac));
  }
  Private Static String GetMacadress ()
  {
    Return NetworkInterface.GetallnetworkInterfaces (). WHERE (NIC = & GT; Nic.OperationalStatus == OperationalStatus.up)
      .Select (nic = & gt; nic.getphysicaladdress (). Tostring ()). FirstOrdefault ();
  }
  Private Static String GetNumbersFromMac (String Mac)
  {
    String TMpdigit = regex.replace (Mac, @ "[^ 0-9] +", string.empty);
    String GetPositionNumber = String.Empty;
    Foreach (Char Number in Tmpdigit)
    {
      GetPositionNumber + = Number * 129/258;
    }
    Return GetPositionNumber;
  }
  Private Static String GetmirroDcharsfrommac (String Mac)
  {
    String Tmpletter = Regex.Replace (Mac, @ "[^ A-Z] +", string.empty);
    string getmirroored = string.empty;
    for (int i = tmpletter.length; i & gt; 0; i--)
    {
      getmirrored + = (tmpletter [i - 1]);
    }
    Return GetMirrored;
  }
}