Check box cell values are intended either for storage, like any other data, or for performing bulk operations.
If you want to respond immediately when users click a check box cell, you can handle the DataGridView.CellClick event, but this event occurs before
the cell value is updated.
If you need the new value at the time of the click, one option is to calculate what the expected value will be based
on the current value. Another approach is to commit the change immediately, and handle the DataGridView.CellValueChanged event to respond to it. To commit the change when the cell is clicked, you must handle the DataGridView.CurrentCellDirtyStateChanged event.
In the handler, if the current cell is a check box cell, call the DataGridView.CommitEdit method and pass in the Commit value.
In DataGridView.CurrentCellDirtyStateChanged Event msdn document, it gives an example:
// This event handler manually raises the CellValueChanged event
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