When you get to the point where you want to write a property editor, you should also be at a point where you are comfortable reading books on Delphi, and reading Delphi code. Basically, they allow you to provide yourself or another developer with a simple and integrated way to change the values of key properties in your component. Property editors typically are designed to operate within the object inspector, though they can also produce dialog windows which appear separately from the object inspector. Property editors inherit at least from TPropertyEditor, but can also inherit from TStringProperty or a variety of other specialized property editors discussed in the Component Developer's Guide and in the on-line help. Property editors need to know both about the property they are editing and the component in which that property exists.
Calls exist for the property editor to access the value of the property.
Getting information about the component, on the other hand. This property editor is to be used on a TDataSet based component. It will retrieve the names of the fields from that component and allow the user to select one, which will then be stored in the property. The property type is defined in the article on Streaming Classes . It wraps a simple AnsiString.