Persist data in XML data island

[Pat Alessi]

I want to use an XML data island to display editable records to a user
on the cleint side. The user should be able to scroll through the
records, modify any or all fields in any or all records, add records,
and delete records.

As far as I can see, there are a couple of ways to implement this. I
could persist the original data island and create a duplicate data
island that the user would modify. When the modifications were
complete, I could post back both XML snippets and compare them to see
what has changed.

Alternatively, I was thinking about using the DiffGram idea, where
each change would add an xml element to an xml snippet that would
indicate what item was changed, added, deleted, etc.

I know that I am not the first person to want to use this type of
technique, so I was hoping that there is something built into the .Net
framework to help with the management of the data. Ideally, I would
like to do something like serialize a dataset to XML, send it to the
client as an XML data island, have them manipulate it, repost it, and
then turn it "magically" into a batch update to the dataset on the
server side. Is that possible, or do I have to roll my own solution?

Thanks.

Pat

 

[Rick Spiewak]

If you read the XML back into a dataset, then you can use .getchanges on the
datatable to get only the changed rows. Send this back to the server in a
dataset. One easy way to do this is to use web services on the server.

 

[Pat Alessi]

So, I could create a dataset, serialize it and send it down to the
client. Then, on the client side, I could bind it to some controls,
let the user add, delete, and modify records. Then, on repost, I
should convert the data back into a dataset, and call .getchanges? I
don't see how getchanges would work without having the original
dataset to compare the new dataset to?

How could I implement this with web services without posting the
information back to the server for every change?

Pat

 

[Rick Spiewak]

Don't bind to the XML, re-create the dataset. Then you can do getchanges
against the modified table, re-create a dataset with just the changes,
and send that back up to the server.