Sorting CheckedListBox for selected items in the list

Question

Hello, I am new to this forum and C# in general. I have a CheckedListBox control that I would like to sort for selected items and then all the following unselected items would be sorted alphabetically. In other words, the selected items would appear at the top of the list in the GUI (and don't necessarily have to be in alphabetical order) and then all the unchecked items after this would be in alphabetical order. Any suggestions for going about this would be great. Also, if this has already been done by someone a point in the right direction (code example) would be greatly appreciated. Thanks in advance for any help. Newell