gridview search problems

In my application , I am populating all the store items and binding to the gridview. Actually i am binding all the arraylist objects  to gridview. (this is static case). Now  my administrator wants to add store items  from the UI to the same gridview which is already populated by static arraylist objects . How to do that ? can any one give an example ? thanks in advance

And the important task for me is , after adding items from UI to gridview  I want to search for some item say ""bookfile""   in the gridview .how to do that ? ---***
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