C# 使用mailkit检查附件大小

我正在下载具有以下代码的给定mailid的附件：

HeaderSearchQuery searchCondition = SearchQuery.HeaderContains("Message-Id", ssMailItemId);

                var folder = client.GetFolder(ssFolderName);
                folder.Open(FolderAccess.ReadOnly);

                IList<UniqueId> ids = folder.Search(searchCondition);

                foreach (UniqueId uniqueId in ids)
                {
                    MimeMessage message = folder.GetMessage(uniqueId);

                    foreach (MimeEntity attachment in message.Attachments)
                    {
                        ssAttachmentsDetail.Append(fillAttachmentDetailRecord(attachment, uniqueId.Id.ToString()));
                    }

HeaderSearchQuery searchCondition=SearchQuery.HeaderContains（“邮件Id”，ssMailItemId）；
var folder=client.GetFolder（ssFolderName）；
folder.Open（FolderAccess.ReadOnly）；
IList ids=文件夹.Search（searchCondition）；
foreach（ID中的UniqueId UniqueId）
{
mimessage message=folder.GetMessage（uniqueId）；
foreach（message.Attachments中的MimeEntity附件）
{
附加（fillAttachmentDetailRecord（附件，uniqueId.Id.ToString（））；
}

---

但是MimeEntity.ContentDisposition.Size和MimePart.ContentDuration都是空的。是否有任何关于附件大小的字段？

只有在

内容处置

标题具有大小参数时才会设置

ContentDisposition.Size

属性，如下所示：

// specify that we want to fill the IMessageSummary.Body and IMessageSummary.UniqueId fields...
var items = folder.Fetch (ids, MessageSummaryItems.BodyStructure | MessageSummaryItems.UniqueId);
foreach (var item in items) {
    foreach (var attachment in item.Attachments) {
        // 'octets' is just a fancy word for "number of bytes"
        var size = attachment.Octets;

        // download the individual attachment
        var entity = folder.GetBodyPart (item.UniqueId, attachment);
    }
}

内容配置：附件；大小=15462

但无论如何，这个值都不应该被信任

如果您想要附件的大小，唯一准确的方法是执行以下操作：

// specify that we want to fill the IMessageSummary.Body and IMessageSummary.UniqueId fields...
var items = folder.Fetch (ids, MessageSummaryItems.BodyStructure | MessageSummaryItems.UniqueId);
foreach (var item in items) {
    foreach (var attachment in item.Attachments) {
        // 'octets' is just a fancy word for "number of bytes"
        var size = attachment.Octets;

        // download the individual attachment
        var entity = folder.GetBodyPart (item.UniqueId, attachment);
    }
}