IE and "out of memory"

[Carlin]

We have a page which is getting the results of a file system folder/file scan that will occasionally throw an ":out of memory" pop-up to the user (and the list of folders which is within a RadListBox, will actually flow over the box boundaries and down off the bottom of the page); close the browser, re-launch and log in and hit the same page again and it will work just fine.

Below is the sub that scans the file system & loads the list - it seems to all work ok every time - it is the rendering that seems to be taking the hit.

My dev team is not able to identify any specific causes for this - was wondering if anyone has seen this or has any suggestions for debugging or correction.  

    Private Sub LoadItems(Optional ByVal bolClearText As Boolean = True)
        If bolClearText Then
            lblFinished.Text = ""
        End If
        If txtIngestServerPath.Text.Trim = "" Then Exit Sub
        Dim dir As IO.DirectoryInfo
        Try
            dir = New IO.DirectoryInfo(txtIngestServerPath.Text.Trim)
        Catch
            lstTemplateFiles.Items.Clear()
            lstRadTemplateFiles.Items.Clear()
            Dim intLanguageCode As Integer = SystemLanguages.SystemLanguages.GetInstance().LanguageCodeForID(userinfo.DefaultLanguage)
            lblFinished.Text = Global.Castnet.App.Language.CastnetInterpreter.InternationalizeString("Invalidfolderpath", intLanguageCode)
            Exit Sub
        End Try
        lstTemplateFiles.Items.Clear()
        lstRadTemplateFiles.Items.Clear()
        If dir.Exists Then
            If Not dir.Parent Is Nothing Then
                Dim item As New RadListBoxItem
                item.Text = "..."
                item.Value = ""
                item.Attributes("itemtype") = "0"
                item.ImageUrl = Resources.ImagePaths.ParentDirectoryIcon
                lstRadTemplateFiles.Items.Add(item)
            End If
            'If Recurse.Checked() Then
            'ParseDirectory(dir)
            'Else
            Dim folders As System.IO.DirectoryInfo = New System.IO.DirectoryInfo(txtIngestServerPath.Text.Trim)
            For Each Folder As System.IO.DirectoryInfo In folders.GetDirectories
                Dim item As New RadListBoxItem
                'item.Text = Folder.FullName.Replace(txtIngestServerPath.Text.Trim, "")
                item.Text = Folder.Name
                item.Value = Folder.FullName
                item.ImageUrl = Resources.ImagePaths.FolderIcon
                item.Attributes("itemtype") = "1"
                lstRadTemplateFiles.Items.Add(item)
            Next

            Dim files As IO.FileInfo() = dir.GetFiles("*.sca")
            Dim fileName As IO.FileInfo
            For Each fileName In files
                'Dim li As New ListItem
                'li.Text = fileName.FullName.Replace(txtIngestServerPath.Text.Trim, "")
                'li.Value = fileName.FullName
                'lstTemplateFiles.Items.Add(li)
                Dim item As New RadListBoxItem
                'item.Text = fileName.FullName.Replace(txtIngestServerPath.Text.Trim, "")
                item.Text = fileName.Name
                item.Value = fileName.FullName
                item.ImageUrl = Resources.ImagePaths.TemplateIcon
                item.Attributes("itemtype") = "2"
                lstRadTemplateFiles.Items.Add(item)
            Next
            'End If
            objContentPage.AjaxManager.ResponseScripts.Add("ScrollToTop();")
        Else
            Dim intLanguageCode As Integer = SystemLanguages.SystemLanguages.GetInstance().LanguageCodeForID(userinfo.DefaultLanguage)
            lblFinished.Text = Global.Castnet.App.Language.CastnetInterpreter.InternationalizeString("Notemplatefilesexistsinselectedfolder", intLanguageCode)
        End If
    End Sub

[T. Tsonev]

Hello Carlin,

Thank you for the detailed description of the problem.

How many items do you add to the RadListBox when the problem occurs?

If you're loading lots of items you might consider using RadTreeView with load-on-demand as an alternative.

I hope this helps.

All the best,
Tsvetomir Tsonev
the Telerik team

[Carlin]

Anywhere from 5 to 30; if we close the browser & start a new session, it will work that 2nd time 99 % of the time.    I believe we had considered a tree view, but from what I can recall, there was something that was more difficult or something that we needed to do that could not easily be done. 

[T. Tsonev]

Hello Carlin,

The number of items is very low and shouldn't be a problem. An out of memory error is very rare and the cause is still unclear at this point.

Let's try working this out step by step. Start with running the browser from the "Internet Explorer (No Add-ons)" shortcut.

The next thing we should try is to remove everything else from the page. If that helps, start adding it back in small steps.

You might also want to run the page through an XHTML validator to check for malformed tags and such. You can use the online service at W3C or this excellent Firefox plugin.

I hope this helps.

Kind regards,
Tsvetomir Tsonev
the Telerik team