private void valider_Click(object sender, EventArgs e) { ClientAjoute clientAjoute = new ClientAjoute(); DBConect db = new DBConect(); db.Initialize(); string identifiant; DateTime dateValue; dateValue = dateTimePicker1.Value; string MySQLFormatDate = dateValue.ToString("yyyy-MM-dd HH:mm:ss"); identifiant = Prenom.Text.Substring(0, 1) + Nom.Text; db.insererClient(Nom.Text, Prenom.Text, Adresse1.Text, Adresse2.Text, Téléphone.Text, Mail.Text, MySQLFormatDate); clientAjoute.Show(); this.Hide(); }