Can someone help me why it doesn\'t work?
I have a checkbox and if I click on it,
this should uncheck all the checkbox inside the datagridview which were check
I had the same problem, and even with the solutions provided here it did not work. The checkboxes would simply not change, their Value would remain null. It took me ages to realize my dumbness:
Turns out, I called the form1.PopulateDataGridView(my data) on the Form derived class Form1 before I called form1.Show(). When I changed up the order, that is to call Show() first, and then read the data and fill in the checkboxes, the value did not stay null.