private void btnEiLegen_Click(object sender, EventArgs e)
{
IGefluegel huhn = cbxTiere.SelectedItem as IGefluegel;
huhn?.EiLegen();
pgdTier.SelectedObject = huhn;
}
private void btnFuettern_Click(object sender, EventArgs e)
{
IGefluegel huhn = cbxTiere.SelectedItem as IGefluegel; // SafeCast: Liefert null, wenn Cast fehlschlägt
if (huhn != null)
{
huhn.Fressen();
pgdTier.SelectedObject = huhn;
}
// Umgang mit Nullables
//int? a = null;
//System.Nullable<int> b = null;
//int c = (a.HasValue ? a.Value : -1);
//int d = a ?? -1;
}
// Speichern
private void button2_Click(object sender, EventArgs e)
{
IGefluegel tier = cbxTiere.SelectedItem as IGefluegel;
if (tier != null)
{
// Speicherort abfragen
SaveFileDialog fileDialog = new SaveFileDialog()
{
Filter = "Hühner|*.hn|Gänse|*.gs|Alles|*.*",
FilterIndex = 0
};
if (fileDialog.ShowDialog() == DialogResult.OK)
{
using (StreamWriter writer = new StreamWriter(fileDialog.FileName))
{
// Tier dort speichern (Serialisierung)
XmlSerializer serializer = new XmlSerializer(tier.GetType());
serializer.Serialize(writer, tier);
}
}
}
}
