The property is used in VFP implementation. The VFP fires "Invalid Subscript Range" error, while it tries to process a number grater than 65000. Since, the HITEM is a long value that most of the time exceeds 65000, the VFP users have to use this property, instead passing directly the handles to properties.

The following VFP sample shows how to change the image of the first item:

.Items.DefaultItem = .Items.AddItem("Item 1")
.Items.CellImage(0,1) = 2

In VFP, the following sample generates an "Invalid Subscript Range" error:

i = .Items.AddItem("Item 1")
.Items.CellImage(i,1) = 2

This happens because the value returned by AddItem is greater than 65000. VFP interprets the CellImage property as an array when the first parameter is a variable with such a value, even though CellImage is a property and not an array.

To avoid this VFP limitation, pass zero as the Item parameter. When the Item parameter is zero, the control uses the item specified by the DefaultItem property instead.

Therefore, you can set the DefaultItem property to the desired item and then use zero as the Item parameter, as shown in the first example.

This is a VFP limitation.