Adds an item to a list box or a combo box.
expression.AddItem(Text, Index)
expression Required. An expression that returns a ControlFormat object.
Text Required String. The text to be added
Index Optional Variant. The position of the new entry. If the list has fewer entries than the specified index, blank items from the end of the list are added to the specified position. If this argument is omitted, the item is appended to the existing list.
Remarks
Using this method clears any range specified by the ListFillRange property.
Example
This example creates a list box and fills it with integers from 1 to 10.
With Worksheets(1)
Set lb = .Shapes.AddFormControl(xlListBox, 100, 10, 100, 100)
For x = 1 To 10
lb.ControlFormat.AddItem x
Next
End With