[Jack Eagles1]

I have a simple RSS reader in a Web Browser application I am making. But whenever I click "Show RSS feeds" which makes my RSS reader window show, my application goes non-responsive!!!! VB 2008 isn't registering any errors or warnings! Help please!

[krum110487]

please post code, we can't find the problem without the source :-D

[Jack Eagles1]

Ok, i am now yeilding an error when trying to show the RSS reader form. Here it is:

The CLR has been unable to transition from COM context 0x209a20 to COM context 0x209b90 for 60 seconds. The thread that owns the destination context/apartment is most likely either doing a non pumping wait or processing a very long running operation without pumping Windows messages. This situation generally has a negative performance impact and may even lead to the application becoming non responsive or memory usage accumulating continually over time. To avoid this problem, all single threaded apartment (STA) threads should use pumping wait primitives (such as CoWaitForMultipleHandles) and routinely pump messages during long running operations.


Here is my code for the RSS reader:

Imports System.IO
Imports System
Imports System.Xml
Imports System.Net
Public Class FeedBrowser1
	Dim webc As New WebClient
	Dim RssURL As String
	Dim Node As System.Xml.XmlNode
	Dim objRSSItem As RSSItem
	Public XmlDoc As New XmlDocument
	Public TempDump As String
	Public Null As Boolean
	Dim OnClose As Boolean = False
	Dim sValue As String
	Public sPath As String = Application.StartupPath & "\Index.ini"
	Dim SectionArray As String
	Dim i As Integer = 0
	Public Shared Title As String
	Dim mine As Boolean = False
	Dim Locationload As Boolean = True
	Dim Errors(2) As String
	Dim UpdateTime As Integer

	Public Class RSSItem
		Public Title As String
		Public Link As String
		Public Description As String
	End Class
	Private Sub FeedBrowser_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
		If OnClose <> True Then
			If INIRead(Application.StartupPath & "\Config.ini", "Config", "OnExit", "Unknown") = "Prompt" Then
				Select Case MsgBox("Are you sure you want to exit?", vbYesNo)
					Case vbNo
						e.Cancel = True
						Exit Sub
					Case vbYes
						NotifyIcon1.Visible = False
						If Me.WindowState = FormWindowState.Minimized Then
						End If
				End Select
			ElseIf INIRead(Application.StartupPath & "\Config.ini", "Config", "OnExit", "Unknown") = "SysTray" Then
				e.Cancel = True
				NotifyIcon1.Visible = True
				Me.Hide()
				Exit Sub
			End If
		End If
		NotifyIcon1.Visible = False
		If Me.WindowState <> FormWindowState.Minimized Then INIWrite(Application.StartupPath & "\Config.ini", "Config", "WindowState", Me.WindowState.ToString)
	End Sub
	Public Function FolderExists(ByVal FolderPath As String) As Boolean
		Dim f As New IO.DirectoryInfo(FolderPath)
		Return f.Exists
	End Function

	Public Function FileExists(ByVal FileFullPath As String) As Boolean
		Dim f As New IO.FileInfo(FileFullPath)
		Return f.Exists
	End Function
	Public Sub FeedProperties()
		Dim frm4 As New Feed_Properties
		Feed_Properties.Owner = Me
		Feed_Properties.Visible = True
	End Sub

	Public Sub EditFeed()
		Dim frm3 As New Edit_Feed
		Edit_Feed.Owner = Me
		Edit_Feed.Visible = True
	End Sub
	Private Sub FeedBrowser_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
		If FolderExists(Application.StartupPath & "\XML") = False Then
			Try
				MkDir(Application.StartupPath & "\XML")
			Catch ex As Exception
				MsgBox("Critical error, could not create directory 'XML' in the installation directory " & vbCrLf & Application.StartupPath)
			End Try
		End If
		Null = False
		If INIRead(Application.StartupPath & "\Config.ini", "Config", "UpdateFeedsonload", "Unknown") = "1" Then
			Dim Thread As New System.Threading.Thread(AddressOf UpdateFeeds)
			Thread.IsBackground = True
			Thread.Priority = Threading.ThreadPriority.Normal
			Thread.Start()
		Else
			RefreshFeeds()
		End If
		RefreshCombo()
		Null = True
		Me.KeyPreview = True
		UpdateTime = INIRead(Application.StartupPath & "\Config.ini", "Config", "CheckInterval", "Unknown")
		If INIRead(Application.StartupPath & "\Config.ini", "Config", "WindowState", "Unknown") = "Maximized" Then
			Me.WindowState = FormWindowState.Maximized
		ElseIf INIRead(Application.StartupPath & "\Config.ini", "Config", "WindowState", "Unknown") = "Normal" Then
			Me.WindowState = FormWindowState.Normal
		End If
		Try
			Me.Location = New System.Drawing.Point(INIRead(Application.StartupPath & "\Config.ini", "Config", "X", "Unknown"), INIRead(Application.StartupPath & "\Config.ini", "Config", "Y", "Unknown"))
		Catch
		End Try
		Locationload = False
	End Sub

	Private Sub FeedBrowser_Locationchanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Locationchanged
		If Locationload = False And Me.WindowState = FormWindowState.Normal Or Me.WindowState = FormWindowState.Maximized Then
			INIWrite(Application.StartupPath & "\Config.ini", "Config", "X", Me.Location.X.ToString)
			INIWrite(Application.StartupPath & "\Config.ini", "Config", "Y", Me.Location.Y.ToString)
		End If
	End Sub

	Private Delegate Sub UpdateFeedsDelegate()
	Public Sub UpdateFeeds()
		If Me.Label2.InvokeRequired Then
			Me.Label2.Invoke(New MethodInvoker(AddressOf UpdateFeeds))
			Exit Sub
		Else
			Errors(0) = ""
			Errors(1) = ""
			Errors(2) = ""
			Dim MyDate As DateTime = New DateTime(Now.Year, Now.Month, Now.Day, Now.Hour, Now.Minute, Now.Second)
			Me.Label2.Show()
			i = 1
			TempDump = ""
			sValue = INIRead(sPath)
			sValue = sValue.Replace("MadeGroups", "")
			sValue = sValue.Replace(ControlChars.NullChar, "|"c)
			Dim splitStrings As String() = sValue.Split(New Char() {"|"c})
			Do Until splitStrings(i) = ""
				sValue = INIRead(sPath, splitStrings(i), "Feed_Url", "Unknown")
				Try
					webc.DownloadFile(sValue, Application.StartupPath & "\XML\" & splitStrings(i) & ".xml.new")
				Catch ex As Exception
					Errors(0) = Errors(0) & splitStrings(i) & vbCrLf
				End Try
				Try
					System.IO.File.Delete(Application.StartupPath & "\XML\" & splitStrings(i) & ".xml")
				Catch ex As Exception
					Errors(1) = Errors(1) & splitStrings(i) & vbCrLf
				End Try
				Try
					System.IO.File.Move(Application.StartupPath & "\XML\" & splitStrings(i) & ".xml.new", Application.StartupPath & "\XML\" & splitStrings(i) & ".xml")
				Catch ex As Exception
					Errors(2) = Errors(2) & splitStrings(i) & vbCrLf
					System.IO.File.Delete(Application.StartupPath & "\XML\" & splitStrings(i) & ".xml.new")
				End Try
				INIDelete(sPath, splitStrings(i), "Last_Check")
				INIWrite(sPath, splitStrings(i), "Last_Check", MyDate)

				Label2.Text = "Processed " & i + 1 & " feeds total."
				Application.DoEvents()
				i = i + 1

			Loop

			Label2.Text = "Completed."
			RefreshFeeds()
			If Errors(0) = "" And Errors(1) = "" And Errors(2) = "" Then
				'MsgBox("Successully updated all feeds with zero errors", MsgBoxStyle.Information)
			Else
				If Errors(0) <> "" Then
					TempDump = TempDump & "The following feeds failed to download: " & vbCrLf & Errors(0)
				End If
				If Errors(1) <> "" Then
					TempDump = TempDump & "The following feeds failed to be deleted: " & vbCrLf & Errors(1)
				End If
				If Errors(2) <> "" Then
					TempDump = TempDump & "The following feeds failed to be moved: " & vbCrLf & Errors(2)
				End If
				MsgBox(TempDump, MsgBoxStyle.Critical)
			End If
			Label2.Visible = False
		End If
	End Sub

	Public Sub UpdateFeed()
		Errors(0) = ""
		Errors(1) = ""
		Errors(2) = ""
		Dim MyDate As DateTime = New DateTime(Now.Year, Now.Month, Now.Day, Now.Hour, Now.Minute, Now.Second)
		Label2.Visible = True
		i = 1
		TempDump = ""
		sValue = INIRead(sPath, Feeds.SelectedItem, "Feed_Url", "Unknown")
		Try
			webc.DownloadFile(sValue, Application.StartupPath & "\XML\" & Feeds.SelectedItem & ".xml.new")
		Catch ex As Exception
			Errors(0) = Errors(0) & Feeds.SelectedItem & vbCrLf
		End Try

		Try
			System.IO.File.Delete(Application.StartupPath & "\XML\" & Feeds.SelectedItem & ".xml")
		Catch ex As Exception
			Errors(1) = Errors(1) & Feeds.SelectedItem & vbCrLf
		End Try
		Try
			System.IO.File.Move(Application.StartupPath & "\XML\" & Feeds.SelectedItem & ".xml.new", Application.StartupPath & "\XML\" & Feeds.SelectedItem & ".xml")
		Catch ex As Exception
			Errors(2) = Errors(2) & Feeds.SelectedItem & vbCrLf
			System.IO.File.Delete(Application.StartupPath & "\XML\" & Feeds.SelectedItem & ".xml.new")
		End Try
		INIDelete(sPath, Feeds.SelectedItem, "Last_Check")
		INIWrite(sPath, Feeds.SelectedItem, "Last_Check", MyDate)
		Label2.Text = "Processed " & i + 1 & " feeds total."
		Application.DoEvents()
		i = i + 1
		Label2.Text = "Completed."
		RefreshFeeds()

		If Errors(0) = "" And Errors(1) = "" And Errors(2) = "" Then
			MsgBox("Successully updated all feeds with zero errors", MsgBoxStyle.Information)
		Else
			If Errors(0) <> "" Then
				TempDump = TempDump & "The following feeds failed to download: " & vbCrLf & Errors(0)
			End If
			If Errors(1) <> "" Then
				TempDump = TempDump & "The following feeds failed to be deleted: " & vbCrLf & Errors(1)
			End If
			If Errors(2) <> "" Then
				TempDump = TempDump & "The following feeds failed to be moved: " & vbCrLf & Errors(2)
			End If
			MsgBox(TempDump, MsgBoxStyle.Critical)
		End If
		Label2.Visible = False
	End Sub
	Public Sub RefreshFeeds()
		On Error Resume Next
		Feeds.Items.Clear()
		i = 1
		sValue = INIRead(sPath)
		sValue = sValue.Replace("MadeGroups", "")
		sValue = sValue.Replace(ControlChars.NullChar, "|"c)
		Dim splitStrings As String() = sValue.Split(New Char() {"|"c})
		Do Until splitStrings(i) = Nothing
			If ComboBox1.SelectedItem <> "All" Then
				sValue = INIRead(sPath, splitStrings(i), "Group", "Unknown")
				If sValue = ComboBox1.SelectedItem Then
					Feeds.Items.Add(splitStrings(i))
				End If
			Else
				Feeds.Items.Add(splitStrings(i))
			End If
			i = i + 1
		Loop
		Feeds.SetSelected(0, True)
	End Sub

	Public Sub RefreshCombo()
		On Error Resume Next
		ComboBox1.Items.Clear()
		i = 0
		sValue = INIRead(sPath, "MadeGroups")
		sValue = sValue.Replace(ControlChars.NullChar, "|"c)
		Dim splitStrings As String() = sValue.Split(New Char() {"|"c})
		Do Until splitStrings(i) = Nothing
			sValue = INIRead(sPath, "MadeGroups", splitStrings(i))
			ComboBox1.Items.Add(sValue)
			i = i + 1
		Loop
		ComboBox1.SelectedIndex = 0
	End Sub

	Private Sub FeedBrowser_Resize(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Resize
		If Me.WindowState = FormWindowState.Minimized Then
			If INIRead(Application.StartupPath & "\Config.ini", "Config", "OnMinimize", "Unknown") = "SysTray" Then
				Me.Hide()
				NotifyIcon1.Visible = True
			End If
		End If
	End Sub

	Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
		Dim frm2 As New Form2
		Form2.Owner = Me
		Form2.Visible = True
	End Sub

	Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
		DeleteFeed()
	End Sub

	Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
		EditFeed()

	End Sub

	Private Sub Button8_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button8.Click
		FeedProperties()
	End Sub

	Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
		NewGroup()
	End Sub

	Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
		EditGroup()

	End Sub

	Private Sub Button6_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button6.Click
		DeleteGroup()
	End Sub

	Private Sub Button9_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button9.Click
		Dim Thread As New System.Threading.Thread(AddressOf UpdateFeeds)
		Thread.IsBackground = True
		Thread.Priority = Threading.ThreadPriority.Normal
		Thread.Start()
	End Sub
	Public Sub NewGroup()
		Dim frm5 As New New_Group
		New_Group.Owner = Me
		New_Group.Visible = True
	End Sub

	Public Sub EditGroup()
		Dim frm6 As New Edit_Group
		Edit_Group.Owner = Me
		Edit_Group.Visible = True
		TempDump = ComboBox1.SelectedIndex
	End Sub

	Public Sub DeleteGroup()
		Dim frm7 As New Delete_Group
		Delete_Group.Owner = Me
		Delete_Group.Visible = True
	End Sub
	Public Sub DeleteFeed()
		Select Case MsgBox("Are you sure you want to delete " & Feeds.SelectedItem & "?", vbYesNo)
			Case vbYes
				IniWriteable()
				If Null = True Then
					INIDelete(sPath, Feeds.SelectedItem)
					Try
						System.IO.File.Delete(Application.StartupPath & "\XML\" & Feeds.SelectedItem & ".xml")
					Catch ex As Exception
						MsgBox("Error deleting feed, XML file not found, or permission was denied", MsgBoxStyle.Critical)
						Exit Sub
					End Try
				End If
		End Select
		RefreshFeeds()
	End Sub
	Public Sub AddFeed(ByVal RssLink As String, ByVal UserTitle As String, ByVal Group As String)
		Try
			XmlDoc.Load(RssLink)
		Catch ex As Exception
			MsgBox("Error loading XML document.  Not a valid RSS feed?", MsgBoxStyle.Critical)
			Exit Sub
		End Try
		IniWriteable()
		If Null = True Then
			Try
				webc.DownloadFile(RssLink, Application.StartupPath & "\XML\" & Title & ".xml")

			Catch ex As Exception
				MsgBox("Error loading XML document.  Not a valid RSS feed?" & Title)
				Exit Sub
			End Try
			MsgBox("Added " & Title & " successfully!", MsgBoxStyle.Information)
			Try
				If Group = Nothing Then Group = "All"
				INIWrite(sPath, Title, "Title", Title)
				INIWrite(sPath, Title, "Feed_Url", RssLink)
				INIWrite(sPath, Title, "Last_Check", File.GetLastWriteTime(Application.StartupPath & "\XML\" & Title & ".xml"))
				INIWrite(sPath, Title, "Group", Group)
				INIWrite(sPath, Title, "Publish_Date", XmlDoc.SelectSingleNode("rss/channel/pubDate").InnerText())
			Catch ex As Exception
			End Try
			RefreshFeeds()
		End If
		Title = Nothing
		UserTitle = Nothing
	End Sub

	Public Sub IniWriteable()
		Try
			Dim fs As New FileStream(Application.StartupPath & "\Index.ini", FileMode.Append, FileAccess.Write)
			Dim s As New StreamWriter(fs)
			s.Close()
		Catch ex As Exception
			MsgBox("Could not write to index file because it's read only." & vbCrLf & Application.StartupPath & "\Index.ini", MsgBoxStyle.Critical)
			Null = False
			Exit Sub
		End Try
		Null = True
	End Sub

	Private Sub Feeds_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Feeds.SelectedIndexChanged

	End Sub
End Class

This is the code to show the RSS reader form:

	Private Sub ButtonX11_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonX11.Click
		FeedBrowser1.Show()

	End Sub

[Jack Eagles1]

Anyone got any ideas?

[Jack Eagles1]

I guess not, I'll try re-writing the RSS code to be incorperated directly in my browser, otherwise if no one has any ideas, I'll give up.

[krum110487]

step through the code and find out what is causing the error!

set a "break" on the load of the RSS then use the "step into" button to go through the code line by line.

this will show you exactly where the error is occuring!