Case 1 :
Generally we can select cell when cell is empty.
Once i assign event to cell than after i can't be able to select that cell again.
When all cell are blank at that time i select some of them using mouse click and drag.
If event was applied to cell and i try to select multiple cell than it does't work.
If selection start with blank cell than it's work, But if i start with assign cell than it does't work.
Please help to sort out this issue.