public static Boolean SupprimerMatiere(string id) { foreach (Matiere item in BDDExterne.GetAllMatiere()) { if (item.matId.ToString() == id) { Debug.WriteLine("on passe là"); NpgsqlConnection conn; conn = new NpgsqlConnection(chaineConnection); conn.Open(); NpgsqlCommand MyCmd = null; // id, nom ,tel,numrue,codepostal,ville,pays,mail,nom rue string query = @"DELETE FROM ""Matiere"" CASCADE WHERE id = '" + id + "'"; Debug.WriteLine(query); MyCmd = new NpgsqlCommand(query, conn); MyCmd.ExecuteNonQuery(); //Exécution conn.Close(); return(true); } } return(false); }