Serializing and Searching Object Collections - vb.net

Question

I would appreciate if somebody could answer some questions regarding storing and searching object collections please. If you could give a basic example of any suggestions I would be very grateful.
Storing:
I'm writing an application which needs to search Active Directory for computer objects, and I'm storing them in a collection of objects. I want to save the computer objects collection along with additional information which is not stored in Active Directory (e.g. the computer's MAC address) for the next time the application is run. I also want to save a list of OU's.
Here is my object collection so far (It will have more properties). What is the best method of saving the collection? Preferably not using a database or will saving to a file have a drastic performance impact?
Or is there a better way to do what I have below?
Public Class Computer
Public Property Name As String
Public Property FQDN As String
Public Property Path As String
End Class
Public Class ComputerCollection
Inherits Collections.CollectionBase
Public Sub Add(ByVal computer As Computer) 'Adds a new computer object to the collection
List.Add(computer)
End Sub
End Class
Searching:
I have a layout similar to ADUC with a tree view of OU's and a list view displaying computer objects in the selected OU. The following code loops through the computer object collection checking if the path of the computer object matches the selected OU path and then displays them in the list view.
Is this the best method in terms of performance? or is there a faster way?
Private Sub tvOU_AfterSelect(sender As Object, e As TreeViewEventArgs) Handles tvOU.AfterSelect
lvComputers.Items.Clear()
If tvOU.SelectedNode.Name > "" Then
For Each computerObj In computers
If computerObj.Path.ToString.Replace("CN=" + computerObj.Name + ",", "") = tvOU.SelectedNode.Name Then
Dim lvItem As New ListViewItem
lvItem.Text = computerObj.Name
lvComputers.Items.Add(lvItem)
End If
Next
Else
Exit Sub
End If
End Sub

Answer 1

A simple List(Of Computer) is indeed all you need unless there is some other unknown requirement. Saving is very simple using serialization for this type of thing, and would work the same for a List or Collection<T>.
Imports System.Collections.ObjectModel
Public Class ComputersCollection
Inherits Collection(Of Computer)
' NOT the crude thing in the VB NameSpace
' there is almost nothing to add: item, add and remove
' are in the base class
' ... perhaps saving and retrieving them by a key (name)
' which may do away with the search procedure in the posted code
End Class
Private Computers As New Collection(Of Computer)
' or
Private Computers As New List(Of Computer)
The other part, saving your collection, can be simple with serialization. First, you will have to add the Serializable attribute to your Computer class:
<Serializable>
Public Class Computer
If you forget, you get the error Class foobar is not marked as serializable. Save to disk:
Imports System.Runtime.Serialization
Private myComputerFile As String = ...
Dim bf As New BinaryFormatter
Using fs As New FileStream(myComputerFile , FileMode.OpenOrCreate)
bf.Serialize(fs, Computers)
End Using
Then you can recreate the List or Collection just as easily; this time the List:
' ToDo: add a check to skip if file is not there
' as in the first time run
Dim bf As New BinaryFormatter
Using fs As New FileStream(myComputerFile , FileMode.Open)
Computers = CType(bf.Deserialize(fs), List(Of Computers))
End Using
Alternatively you can use the XML serializer to create an XML File or use the faster, smarter binary serializer is ProtoBuf-Net