Check box allowing export to datagridview

Question

i have a checkbox in my datagridview in form1 and at the moment it allows to be checked even if the user does not enter a value in the qty. This datagridview is then exported to another datagridview in form2 which is then exported to excel.

Is a there asolution for this or how can i make that the datagridview in form 1 only exports to form2 if qty > 0 

data from sqlite is on form1 and quantity is set to 0. the user has to enter a value >0

 

please assist. I have thew checkbox but this takes long as the user has to enter a value and then click on checkbox. this takes long if there is 30 items .