//PESEL
private void button1_Click(object sender, EventArgs e)
{
Pesel pesel = new Pesel();
if (textBox_PESEL.Text != "" && long.TryParse(textBox_PESEL.Text, out y) &&
textBox_PESEL.Text.Length == 11)
{
MessageBox.Show(pesel.CheckPesel(textBox_PESEL.Text));
}
else if (textBox_PESEL.Text.Length < 11)
{
MessageBox.Show("Pesel is too short");
}
else
{
MessageBox.Show("Write your pesel");
}
}
