I recently found the need to Sync two lists. I have one list that is used for display, and I want to dynamically sync that list with a new one by applying a delta.
I thought that this would be difficult, but I was surprised at its ease.
1 1:
1 2: Module SyncExtensions
1 3:
1 4: <System.Runtime.CompilerServices.Extension()> _
1 5: Public Sub Sync(Of TItem)(ByVal targetItems As ICollection(Of TItem), ByVal sourceItems As IEnumerable(Of TItem))
1 6: Dim o As Object = DirectCast(targetItems, ICollection).SyncRoot
1 7: If Monitor.TryEnter(o, TimeSpan.FromSeconds(10)) Then
1 8: ' Find items in source that are not in target
1 9: Dim itemsToAdd As New Collection(Of TItem)
1 10: For Each Item In sourceItems
1 11: If Not targetItems.Contains(Item) Then
1 12: itemsToAdd.Add(Item)
1 13: End If
1 14: Next
1 15: ' Apply all adds
1 16: For Each Item In itemsToAdd
1 17: targetItems.Add(Item)
1 18: Next
1 19: ' Find tags in target that should not be in source
1 20: Dim itemsToRemove As New Collection(Of TItem)
1 21: For Each Item In targetItems
1 22: If Not sourceItems.Contains(Item) Then
1 23: itemsToRemove.Add(Item)
1 24: End If
1 25: Next
1 26: ' Apply all removes
1 27: For Each Item In itemsToRemove
1 28: targetItems.Remove(Item)
1 29: Next
1 30: ' Dispose Timer
1 31: Monitor.Exit(o)
1 32: End If
1 33: End Sub
1 34:
1 35: End Module
You need to remember to lock the object while you sync. This is to allow your threading to take place without incident. The nitty gritty is just a case of comparing the two lists and building a list of changes to make and then removing them :)
Technorati Tags: .NET
No related videos found.
If you've made it this far, it's worth connecting with our principal consultant and coach, Martin Hinshelwood, for a 30-minute 'ask me anything' call.
We partner with businesses across diverse industries, including finance, insurance, healthcare, pharmaceuticals, technology, engineering, transportation, hospitality, entertainment, legal, government, and military sectors.
Teleplan
Philips
Jack Links
Xceptor - Process and Data Automation
Cognizant Microsoft Business Group (MBG)
SuperControl
Qualco
Genus Breeding Ltd
YearUp.org
Capita Secure Information Solutions Ltd
Illumina
Workday
Akaditi
Kongsberg Maritime
Milliman
ProgramUtvikling
Sage
Emerson Process Management
Department of Work and Pensions (UK)
Nottingham County Council
Washington Department of Transport
New Hampshire Supreme Court
Royal Air Force
Washington Department of Enterprise Services
Schlumberger
Graham & Brown
New Signature
Illumina
DFDS
Xceptor - Process and Data Automation