private void button4_Click(object sender, EventArgs e)
{
int key;
string txt;
MyCaesarCipher.AutoDecrypt(txtCipher.Text.ToLower(), out key, out txt);
numKey.Value = key;
txtPlain.Text = txt;
}
private void button1_Click(object sender, EventArgs e)
{
txtCipher.Text = MyCaesarCipher.Encrypt(txtPlain.Text.ToLower(), (int)numKey.Value);
}