No, sorry it doesn't work like that.
When the user clicks on any row in the DataGridView, he can't simultaneously click on a delete button in your form: he only has one mouse pointer!
What are you actually trying to achieve, because I think your implemenation is getting a little confused!
"sorry, i confused. here i tell u exactly what needs to be, we should select any row and if we click delete button it'll show another form. how would it achieved. reply me"
Please do not use the "Add answer" button - if you use "Add Comment" then I get an email, rather than my looking back at some point in the future. You generally get a quicker response that way!
As Espen Harlinn says, The DGV has a SelectedRows property which you can iterate through in your Button click event:
foreach (DataGridViewRow row in myGrid.SelectedRows)
{
...
}
You can then assemble whatever information you want and show your second form.