Deleting a row from gridview bound manually? - asp.net

Question

I have a gridview which is bound to a table that allows to download files. The table consists of:
tableid as int
filename as string
filepath as string
delete (added column in the gridview)
This deletion is not automatic, it is coded. I want the user to click on delete and the row selected will be deleted. Simple as that, but I cant seem to get the ID of the row to be deleted. This is what I have done:
Try
'Get the Image_Id from the DataKeyNames
Dim imgId As Integer = Convert.ToInt32(gvDetails.DataKeys(e.RowIndex).Value)
Dim cmd As New SqlCommand("delete from FilesTable where id=#id", con)
cmd.Parameters.AddWithValue("#id", imgId)
cmd.CommandType = CommandType.Text
con.Open()
cmd.ExecuteNonQuery()
Catch ex As Exception
ScriptManager.RegisterStartupScript(Me, Me.[GetType](), "Message", "alert('Error occured : " & ex.Message.ToString() & "');", True)
End Try
But I keep getting error that string output cannot be converted to Integer:
Error Occurred: Input string was not in a correct format.
Please Help!
This is how the grid view is bound:
Private Sub BindGridviewData()
Try
con.Open()
Dim cmd As New SqlCommand("select * from FilesTable", con)
Dim da As New SqlDataAdapter(cmd)
Dim ds As New DataSet()
da.Fill(ds)
con.Close()
gvDetails.DataSource = ds
gvDetails.DataBind()
Catch ex As Exception
Response.Write(ex.Message)
End Try
End Sub

Answer 1

I found the answer after a long time and it was a simple problem:
Instead of:
Dim imgId As Integer = Convert.ToInt32(gvDetails.DataKeys(e.RowIndex).Value)
I changed it into:
Dim imgId As Integer = Int32.Parse(gvDetails.Rows(e.RowIndex).Cells(0).Text)