datagrid scrolling question

[James At The Hale]

I am a little lost here as to why this is a DG question as such.
Certainly being able to dynamically fill data within a row is a great UI feature when the user is directly interacting with a row.
But it seems you wish to completely fill particular values in all the rows from outside the DG.
In this case, why not operate directly on the DGdata, loop through the array, fill in all the required values and then send the whole array back to the DG?