... Products list box and then click on the arrow button pointing to the right (>), then the item is moved to the Selected Products list box If you select items in the Selected Products list box and ... box for Unassigned Only is checked, then ' grab the product items where the category is null; otherwise, load ' it up with those products not assigned to the current category If chkUnAssignedOnly.Checked ... Add the code in Listing 8.8 to the Click event of the btnUnSelect command button Again, this code is similar to the previous step, but it is used to set the CategoryID column to null if the product...