how to make the checkboxlist only can select one item

I have 12 set of checkboxlist, i would like to let the users have two option.

1. Only can select one of the item from each checkboxlist

2. Not select any item

My problem is "how to set the checkboxlist to let it only can select one of the item?".  I can't use the radiobuttonlist because it cannot deselect the item. (This will make the option 2 not working).

Can someone provide me the code to "uncheck" other item  in the checkboxlist when a item is checked?  That mean each time, the checkbox only can select one item.

 

 
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