Easyui datagrid 根据条件改变颜色

 Easyui datagrid 根据条件改变颜色：

$("#txtMaterialNum").keydown(function (e) {
                if (e.keyCode != 13 || $.trim($("#txtMaterialNum").val()) == "") return;
                var _mm = $.trim($("#txtMaterialNum").val());
                var rows = $("#datagrid_list").datagrid("getRows");
                var _sn = "";
                for (var i = 0; i < rows.length; i++) {
                    if ($.trim(_mm) == $.trim(rows[i].MATERIAL_SN)) {
                        $("#datagrid-row-r1-2-" + i).css({ "background-color": "green", "color": "white" });
                    }
                }                

            });