How do I show like-values in custom fields in a property grid?

Question

I have a property grid that helps me manage all of the controls on a form. These controls are for designer-type folks, so I'm not really worried that much about the user interface... until someone selects multiple objects.

I have a UITypeEditor for the "BottomDiameter" property on these common objects. It keeps track of units (meters vs feet) and does some nice things on-the-fly. However, when someone selects two or three common objects, BottomDiameter is blank, even though it evaluates to the same text string.

The reason (I think) that it is blank is that it is actually three separate objDiameter objects. How can I tell the property grid to behave like all of the other properties and show the value if it evaluates to the same string???

UPDATE: For example, the "Anchor" property has a text output of "Top, Right" but when you pull it down it is an object. Yet, when you select five objects on your form that all have the same Anchor setting you can still see the string "Top, Right" in the property grid.

Answer 1

In the TypeConvertor of the Datatype which is attributed to BottomDiameter Property, you might want to create a vistor like class called say, BottomDiameterVistor which would take an array or a list of the selected BottomDiameter(s). Override the to string property on the BottomDiameterVistor to return your aggregrated text value for the property.

Answer 2

If your BottomDiameter is a class and not a simple primitive, then you have to override the Equals method in this class.