select option下拉叠加

if (data.rows.length > 0) {
                        $.each(data.rows, function (i, item) {
                            jQuery("#versionId").append("<option value=" + item.versionId + ">" + item.vName + "</option>");
                        });
                    } else {
                        jQuery("#versionId").append("<option value=" + '' + ">" + "----------------------选择升级类型下拉------------------" + "</option>");
                    }