我有表Message,并Image说我的加盟。这些表如下所示:
Message(MessageID, TimeStamp, Text, RoomID, ImageID, UserID)
Image(ImageID, Path, Type, UserID)
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并非所有邮件都有一个ImageID。这是我当前的加入:
List<Message> messages = Message.GetAll();
List<Image> images = Image.GetAll();
var resultTable = from m in messages
join i in images
on m.ImageID equals i.ImageID
select new
{
MessageID = m.MessageID,
TimeStamp = m.TimeStamp,
Text = m.Text,
RoomID = m.RoomID,
ImageID = m.ImageID,
UserID = m.UserID,
Path = i.Path // Nullable
};
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然后resultTable,我绑定到ListView需要表中的Path列的Image。我当前的联接仅返回带有图像的消息。我将如何选择所有消息,但是如果消息中包含ImageID != null …