SPUserStorage class
Maintains information about the user of a Web Part Page and the amount of space the user is consuming in bytes.
Namespace: Microsoft.SharePoint
Assembly: Microsoft.SharePoint (in Microsoft.SharePoint.dll)
This class serves two purposes in managing Web Part personalizations:
Provides information about the amount of memory consumed by the personalizations of a user.
Reduces the amount of space used on the server because the UserId property for a user-storage object can be passed as the parameter in the DeleteAllPersonalizations method of the SPFile class when deleting the personalizations for a particular user.
Use the LengthByUser property of the SPFile class to return an SPUserStorageCollection object that contains information about each user of a Web Part Page. Use an indexer to return a single user-storage object from the collection. For example, if the collection is assigned to a variable named myUserStorages, use myUserStorages[index] in C#, or myUserStorages(index) in Microsoft Visual Basic, where index is the index number of the user storage in the collection. You can also use a foreach statement (For Each in Visual Basic) to iterate through the collection and return the user storage objects.