delphi 2010 datasnap从服务器返回树视图

Question

is it possible in Delphi Datasnap 2010 to transfer treeview from Datasnap 2010 server to DataSnap Client?

thanks

Answer 1

You might be able to kludge something together that creates and populates a VCL control on the server and serialize the control to the client, but it seems ugly.

I would have it return the data that represents a tree and use that to populate a treeview on the client side, instead.

NodeId  NodeName  ParentId
0       Root      -1
1       Node1     0
2       Node2     0
3       Node3     0
4       Node1.1   1

Answer 2

Instead of transferring GUI elements from servers to clients, it is a common practice to transfer the data only (for example as 'data transfer objects', DTO) which can easily be (de-)serialized using open source libraries like OmniXML , NativeXML or SuperObject .

The presentation layer can change easily (think of HTML or mobile clients) this way.

The definition for DTO can be found on Martin Fowler's site.

Answer 3

DataSnap can serialize objects using JSON. I recommend you create a tree structure in which you would store the nodes and then populate your treeview accordingly.

And no, you cannot serialize a VCL TTreeView.