the good old problem of getting the data from the row that is being currently edited within a Grid View. Accessing the "Controls": This method gets you access to the control in the Grid View, which might be useful based on what you are doing.
Obviously the simplest method is to use Data Key Names on the Grid View and then you should have the data in your Grid View Update Event Args as part of e. (In the following example, I cast to a Check Box as I know I have a checkbox at the col Index You Are Interested In - you should cast to whatever control you have in that column).
This will lead to problems like "Grid View does not show updated values", "Grid View looses values changed by user". In your Page_load, this is typically only inside a block where you check to make sure that Page_Load is not being called during a post-back call.
For a while now I’m trying to figure out why my method, triggered by the Grid View.
In my case this was happening because I was binding to a List of custom objects.