Rank: Newbie
Groups: Member
Joined: 9/29/2009
Posts: 5
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Hi all,
I'm new in this treeview thing. And I have a problem !!
I have a large Treeview, and I want to cache the Treeview in a web page, just so that on e.g postback I don't have to populate the treeview again.
I can cache the Treeview, but when I cast it back it is blank. No treeview is displayed, but in debug, I can see that alle the Nodes are there.
This is possible not the correct way, can anybody help ?
Code behind:
Dim myTree As EO.Web.TreeView
If Not (CType(Cache.Get("myNode"), EO.Web.TreeView) Is Nothing) Then
myTree = CType(Cache.Get("myNode"), EO.Web.TreeView)
Try
'TreeView1 is the treeview on webpage
TreeView1 = myTree
Catch ex As Exception
teststring = " error: " + ex.Message
End Try
Else
'This creates a very complexed treeview.
createTreeviewTest(False)
Cache.Insert("myNode", TreeView1)
End If
asp.net:
<eo:TreeView ID="TreeView1" runat="server" Height="999px" Width="210px" SingleExpandMode="AllLevels"
EnableViewState="False" StateCookieName="myTreeKage" EnableKeyboardNavigation="True"
AutoCheckParent="True">
<LineImages PlusMinusOnly="False" ImageWidth="12" />
<LookNodes>
<eo:TreeNode ItemID="_Default" RaisesServerEvent="True" >
</eo:TreeNode>
</LookNodes>
</eo:TreeView>
Regards,
Torben
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Rank: Administration
Groups: Administration
Joined: 5/27/2007
Posts: 24,194
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Hi,
No. You can't cache the TreeView that way. Assigning TreeView1 another value points TreeView1 to the TreeView object in your memory. It does not replace/rebuilt the TreeView in your page.
If you do not wish to populate the TreeView every time, you can load the data into a DataSet/DataTable (depending on how you populate it originally), then place that DataSet/DataTable object in your cache. You will still be populating the TreeView from the cached DataSet/DataTable object every time. But you only fill the DataSet/DataTable from your DB once.
Thanks!
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Rank: Newbie
Groups: Member
Joined: 9/29/2009
Posts: 5
|
Hi,
Thanks for your fast reply.
Okay, I just hoped for the quick solution (-:
Regards,
Torben
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Rank: Administration
Groups: Administration
Joined: 5/27/2007
Posts: 24,194
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You are welcome. Let us know if you have any other questions!
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