Thank you for writing back.
There are two ways to achieve what you want.
1. You can create an in-place popup to edit the row. Here is how to do that: http://www.telerik.com/support/kb/winforms/gridview/details/create-pop-up-user-control-for-row-editing
2. You can subscribe to the CurrentRowChanged event, which will get triggered when the current row in the grid is changed, and in it, open the desired form of yours by passing the row to it, edit the row cells, and close the form when you are done.
I hope that this will work for you. Let us know should you have any other questions.
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