asp:table remembering state?

9 Jun 2005 9:19 AM

Davey P

I have an asp.net table which I am populating with controls dynamically at
runtime. The controls themselves get/set values in a datatable which is
stored in viewstate over postbacks. Here is basically what I am doing:

pull datatable out of viewstate

for each row in datatable
   create tablerow
   create tablecells
   create controls
   get data items from datatable and place the values in the controls
   add controls to tablecells
   add tablecells to tablerow
   add tablerow to asp table

draw the control

I save values back to the datatable in a similar way, but instead scroll
through the rows in the asp table and place the values in the appropriate
datatable item.
This all works fine, but the problem is with deleting a row. I simply delete
the desired row from the datatable and then call my table creation method
described above. This should surely mean that the asp table will not display
the row as it no longer exists in the datatable. But what happens is that a
row is deleted, but all the ones below it "bubble up" in that they take on
the previous rows value. So it seems as if the bottom row has been removed.
I've checked my datatable and the values in here don't correspond with whats
being displayed. Is there some form of caching going on that I'm not seeing?
ViewState is turned off for the asp table and hence all of its controls.

Any ideas?!!!

(p.s. sorry for the long description, but I thought I'd try and give you a
clear picture of whats going on)

10 Jun 2005 6:34 PM

lisa

Hi Davey,

Items in ViewState get saved in order. If you get rid of items, that
doesn't change. And I'm not 100% sure that turning off ViewState for
the table is going to turn it off for the controls in the cells.

Try this: http://www.wilsondotnet.com/Demos/ViewState.aspx

This is a ViewState parser. It doesn't tell you the names of the
controls, because, as I said, it relies completely on the order in
which they are saved to ViewState and loaded from ViewState. But if
you have values in the controls, odds are you'll be able to figure out
what's what.

At the very least, should all else fail, you could simply hide rows
instead of deleting them. Setting Visible = False will keep them from
being rendered, but will preserve the order for your ViewState. Of
course, if you decide to try sorting the rows, that wouldn't help you
anymore, but you haven't said anything about doing that.

Lisa

Davey P wrote:
Show quoteHide quote

> I have an asp.net table which I am populating with controls dynamically at
> runtime. The controls themselves get/set values in a datatable which is
> stored in viewstate over postbacks. Here is basically what I am doing:
>
> pull datatable out of viewstate
>
> for each row in datatable
>    create tablerow
>    create tablecells
>    create controls
>    get data items from datatable and place the values in the controls
>    add controls to tablecells
>    add tablecells to tablerow
>    add tablerow to asp table
>
> draw the control
>
> I save values back to the datatable in a similar way, but instead scroll
> through the rows in the asp table and place the values in the appropriate
> datatable item.
> This all works fine, but the problem is with deleting a row. I simply delete
> the desired row from the datatable and then call my table creation method
> described above. This should surely mean that the asp table will not display
> the row as it no longer exists in the datatable. But what happens is that a
> row is deleted, but all the ones below it "bubble up" in that they take on
> the previous rows value. So it seems as if the bottom row has been removed.
> I've checked my datatable and the values in here don't correspond with whats
> being displayed. Is there some form of caching going on that I'm not seeing?
> ViewState is turned off for the asp table and hence all of its controls.
>
> Any ideas?!!!
>
> (p.s. sorry for the long description, but I thought I'd try and give you a
> clear picture of whats going on)