BeforeProperties/AfterProperties in Event Receivers – Tricky....!

These are the values of the properties in List events:

List	BeforeProperties	AfterProperties	properties.ListItem
ItemAdding	No Value	No Value	Null
ItemAdded	No Value	No Value	New Value
ItemUpdating	Original Value	Changed Value	Original Value
ItemUpdated	Original Value	Changed Value	Changed Value
ItemDeleting	No Value	No Value	Original Value
ItemDeleted	No Value	No Value	Null

And here are the properties available in Library events:

Library	BeforeProperties	AfterProperties	properties.ListItem
ItemAdding	No Value	No Value	Null
ItemAdded	No Value	No Value	New Value
ItemUpdating	Original Value	Changed Value	Original Value
ItemUpdated	Original Value	Changed Value	Changed Value
ItemDeleting	No Value	No Value	Original Value
ItemDeleted	No Value	No Value	Null

Hope this helps!