public static void updateTaskInfoDataGridView(DataGridView taskInfoDataGridView) { MySqlConnection conn = null; try { DataTable dt = (DataTable)taskInfoDataGridView.DataSource; if (dt != null) { dt.Rows.Clear(); taskInfoDataGridView.DataSource = dt; } conn = DatabaseOpt.getDBConnection(); taskInfoDataGridView.DataSource = DatabaseOpt.queryAll(conn); taskInfoDataGridView.Refresh(); } finally { DatabaseOpt.close(conn); } }