Friday, August 10, 2007

Can not retrieve values from grid view

Working with grid view, I faced an issue!

I had a gridview in which I had to hide few columns and use them later on for some conditional checks. The hiding part was quite easy and straight-forward but the conditional check was tricky. When I tried to get the values of the hidden column using
where the hidden column index is 0, null was being returned. This looked strange to me as I was setting the values properly i.e. a datatable was being bound to the gridview and the datatable was properly constructed.

It turned out that ability to retrieve values from hidden columns has been chopped off in the new gridview. The logic that I found out (after a bit of gooling) was that, since most of the users hide primary key columns in the datatable, it is not safe to allow the column values to be retrieved. I guess the first part of the logic is very much right, that primary key columns are the best prospects to hiding. The second part may also be correct, that it is unsafe to expose them. But these two parts together, cause more harm than good!

First of all, inconvenience to devs as the regular functionality is changed. Second, how are the devs expected to identify the rows that the user is operating on? Often, the data in the gridview has a mapping table and if the dev can't retrieve its primary key, what operations are possible on it? And what use is the grid off?

Anyways, there is an easy workaround for this though. If you are in hurry, don't worry about all the blabber above. Just do the hiding of columns after you finish the binding of data. This works!