如何通过office.js读写Outlook event上的开放扩展？

// 获取当前选中的事件
Office.context.mailbox.item.getCallbackTokenAsync({ isRest: true }, function (result) {
    if (result.status === Office.AsyncResultStatus.Succeeded) {
        var token = result.value;
        var ewsId = Office.context.mailbox.item.itemId;
        var restId = Office.context.mailbox.convertToRestId(ewsId, Office.MailboxEnums.RestVersion.v2_0);

        // 构建请求 URL
        var getEventsUrl = Office.context.mailbox.restUrl + "/v2.0/me/events/" + restId;

        // 使用 REST API 获取事件详细信息
        $.ajax({
            url: getEventsUrl,
            headers: { "Authorization": "Bearer " + token },
            success: function (eventData) {
                // 添加开放扩展
                eventData.singleValueExtendedProperties = [
                    {
                        id: "String {00062004-0000-0000-C000-000000000046} Id 0x003F",
                        value: "CustomValue"
                    }
                ];

                // 更新事件
                $.ajax({
                    url: getEventsUrl,
                    type: "PATCH",
                    headers: {
                        "Authorization": "Bearer " + token,
                        "Content-Type": "application/json"
                    },
                    data: JSON.stringify(eventData),
                    success: function () {
                        console.log("开放扩展已成功添加到事件。");
                    },
                    error: function (error) {
                        console.error("添加开放扩展时出错: ", error);
                    }
                });
            },
            error: function (error) {
                console.error("获取事件详细信息时出错: ", error);
            }
        });
    } else {
        console.error("获取回调令牌时出错: ", result.error.message);
    }
});