Enumerating folders always yeilds an error

  • Thread starter Thread starter Jerry West
  • Start date Start date
J

Jerry West

VB 2005 .NET

I'm trying to enumerate through a folder structure. Everytime I try I
receive an error. The error states:

ContextSwitchDeadlock was detected

The CLR has been unable to transition from COM context 0x1a0de0 to COM
context 0x1a0f50 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.

This occurs at various points in the code --almost never at the same point.
I mean jeez, what the heck? I'm definitely new to VB .NET but this was a
cinch in VB6. It looked like it was going to be even easier in .NET but....


The code:

Dim x As New FileSearch(New
IO.DirectoryInfo(ss.s.ImagePath))

x.Recursive = True
x.Search()


Option Strict On
Option Explicit On

Imports System.IO

Public Class FileSearch

Private Const DefaultFileMask As String = "*.*"
Private Const DefaultDirectoryMask As String = "*"

#Region " Member Variables "

Private _FileMask As String
Private _DirectoryMask As String
Private _Recursive As Boolean
Private _InitialDirectory As DirectoryInfo

Private _Files As New List(Of FileInfo)
Private _Directories As New List(Of DirectoryInfo)

#End Region

#Region " Properites "

Public Property Recursive() As Boolean

Get
Return _Recursive
End Get

Set(ByVal Value As Boolean)
_Recursive = Value
End Set

End Property

Public Property InitialDirectory() As DirectoryInfo

Get
Return _InitialDirectory
End Get

Set(ByVal Value As DirectoryInfo)
_InitialDirectory = Value
End Set

End Property

Public Property DirectoryMask() As String

Get
Return _DirectoryMask
End Get

Set(ByVal Value As String)
_DirectoryMask = Value
End Set

End Property

Public Property FileMask() As String

Get
Return _FileMask
End Get

Set(ByVal Value As String)
_FileMask = Value
End Set

End Property

Public ReadOnly Property Directories() As List(Of DirectoryInfo)

Get
Return _Directories
End Get

End Property

Public ReadOnly Property Files() As List(Of FileInfo)

Get
Return _Files
End Get

End Property

#End Region

#Region " Constructors "

Public Sub New()

End Sub

Public Sub New(ByVal BaseDirectory As String, Optional ByVal FileMask As
String = DefaultFileMask, Optional ByVal DirectoryMask As String =
DefaultDirectoryMask)

Me.New(New IO.DirectoryInfo(BaseDirectory), FileMask, DirectoryMask)

End Sub

Public Sub New(ByVal BaseDirectory As DirectoryInfo, Optional ByVal
FileMask As String = DefaultFileMask, Optional ByVal DirectoryMask As String
= DefaultDirectoryMask)

_InitialDirectory = BaseDirectory
_FileMask = FileMask
_DirectoryMask = DirectoryMask

End Sub

#End Region

Protected Overrides Sub Finalize()

_Files = Nothing
_Directories = Nothing
_Recursive = False
MyBase.Finalize()

End Sub

Public Sub Search(Optional ByVal BaseDirectory As DirectoryInfo =
Nothing, Optional ByVal FileMask As String = Nothing, Optional ByVal
DirectoryMask As String = Nothing, Optional ByVal Recursive As Boolean =
False)

If (Not IsNothing(BaseDirectory)) Then _InitialDirectory =
BaseDirectory

If IsNothing(_InitialDirectory) Then Throw New ArgumentException("A
Directory Must be specified!", "Directory")

If Recursive Then _Recursive = Recursive

If IsNothing(_FileMask) And IsNothing(FileMask) Then

_FileMask = DefaultFileMask

ElseIf (Not IsNothing(FileMask)) Then

_FileMask = FileMask

End If

If IsNothing(_DirectoryMask) And IsNothing(DirectoryMask) Then

_DirectoryMask = DefaultDirectoryMask

ElseIf IsNothing(_DirectoryMask) Then

_DirectoryMask = DirectoryMask

End If

DoSearch(_InitialDirectory)

End Sub

Private Sub DoSearch(ByVal BaseDirectory As DirectoryInfo)

Try

_Files.AddRange(BaseDirectory.GetFiles(_FileMask))

Catch u As UnauthorizedAccessException

'Siliently Ignore this error, there isnt any simple
'way to avoid this error.

End Try

If (Not _Recursive) Then Exit Sub

Try

If _Recursive Then

Dim Directories() As DirectoryInfo =
BaseDirectory.GetDirectories(_DirectoryMask)

_Directories.AddRange(Directories)

Else

Dim d As DirectoryInfo = New DirectoryInfo(ss.s.ImagePath)

_Directories.Add(d)

'Dim Directories() As DirectoryInfo = d

End If

For Each di As DirectoryInfo In Directories

DoSearch(di)

Next

Catch u As UnauthorizedAccessException

'Siliently Ignore this error, there isnt any simple
'way to avoid this error.

End Try

End Sub

End Class
 
Jerry West said:
VB 2005 .NET

I'm trying to enumerate through a folder structure. Everytime I try I
receive an error. The error states:

ContextSwitchDeadlock was detected

The CLR has been unable to transition from COM context 0x1a0de0 to COM
context 0x1a0f50 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.

This occurs at various points in the code --almost never at the same
point. I mean jeez, what the heck? I'm definitely new to VB .NET but this
was a cinch in VB6. It looked like it was going to be even easier in .NET
but....


The code:

Dim x As New FileSearch(New
IO.DirectoryInfo(ss.s.ImagePath))

x.Recursive = True
x.Search()


Option Strict On
Option Explicit On

Imports System.IO

Public Class FileSearch

Private Const DefaultFileMask As String = "*.*"
Private Const DefaultDirectoryMask As String = "*"

#Region " Member Variables "

Private _FileMask As String
Private _DirectoryMask As String
Private _Recursive As Boolean
Private _InitialDirectory As DirectoryInfo

Private _Files As New List(Of FileInfo)
Private _Directories As New List(Of DirectoryInfo)

#End Region

#Region " Properites "

Public Property Recursive() As Boolean

Get
Return _Recursive
End Get

Set(ByVal Value As Boolean)
_Recursive = Value
End Set

End Property

Public Property InitialDirectory() As DirectoryInfo

Get
Return _InitialDirectory
End Get

Set(ByVal Value As DirectoryInfo)
_InitialDirectory = Value
End Set

End Property

Public Property DirectoryMask() As String

Get
Return _DirectoryMask
End Get

Set(ByVal Value As String)
_DirectoryMask = Value
End Set

End Property

Public Property FileMask() As String

Get
Return _FileMask
End Get

Set(ByVal Value As String)
_FileMask = Value
End Set

End Property

Public ReadOnly Property Directories() As List(Of DirectoryInfo)

Get
Return _Directories
End Get

End Property

Public ReadOnly Property Files() As List(Of FileInfo)

Get
Return _Files
End Get

End Property

#End Region

#Region " Constructors "

Public Sub New()

End Sub

Public Sub New(ByVal BaseDirectory As String, Optional ByVal FileMask
As String = DefaultFileMask, Optional ByVal DirectoryMask As String =
DefaultDirectoryMask)

Me.New(New IO.DirectoryInfo(BaseDirectory), FileMask,
DirectoryMask)

End Sub

Public Sub New(ByVal BaseDirectory As DirectoryInfo, Optional ByVal
FileMask As String = DefaultFileMask, Optional ByVal DirectoryMask As
String = DefaultDirectoryMask)

_InitialDirectory = BaseDirectory
_FileMask = FileMask
_DirectoryMask = DirectoryMask

End Sub

#End Region

Protected Overrides Sub Finalize()

_Files = Nothing
_Directories = Nothing
_Recursive = False
MyBase.Finalize()

End Sub

Public Sub Search(Optional ByVal BaseDirectory As DirectoryInfo =
Nothing, Optional ByVal FileMask As String = Nothing, Optional ByVal
DirectoryMask As String = Nothing, Optional ByVal Recursive As Boolean =
False)

If (Not IsNothing(BaseDirectory)) Then _InitialDirectory =
BaseDirectory

If IsNothing(_InitialDirectory) Then Throw New ArgumentException("A
Directory Must be specified!", "Directory")

If Recursive Then _Recursive = Recursive

If IsNothing(_FileMask) And IsNothing(FileMask) Then

_FileMask = DefaultFileMask

ElseIf (Not IsNothing(FileMask)) Then

_FileMask = FileMask

End If

If IsNothing(_DirectoryMask) And IsNothing(DirectoryMask) Then

_DirectoryMask = DefaultDirectoryMask

ElseIf IsNothing(_DirectoryMask) Then

_DirectoryMask = DirectoryMask

End If

DoSearch(_InitialDirectory)

End Sub

Private Sub DoSearch(ByVal BaseDirectory As DirectoryInfo)

Try

_Files.AddRange(BaseDirectory.GetFiles(_FileMask))

Catch u As UnauthorizedAccessException

'Siliently Ignore this error, there isnt any simple
'way to avoid this error.

End Try

If (Not _Recursive) Then Exit Sub

Try

If _Recursive Then

Dim Directories() As DirectoryInfo =
BaseDirectory.GetDirectories(_DirectoryMask)

_Directories.AddRange(Directories)

Else

Dim d As DirectoryInfo = New DirectoryInfo(ss.s.ImagePath)

_Directories.Add(d)

'Dim Directories() As DirectoryInfo = d

End If

For Each di As DirectoryInfo In Directories

DoSearch(di)

Next

Catch u As UnauthorizedAccessException

'Siliently Ignore this error, there isnt any simple
'way to avoid this error.

End Try

End Sub

End Class
Click to expand...

I get this message sometimes in long processing while debugging. I simply
ignore the message and continue. It is just telling you that the attached
debugger VS or VB.Express was waiting for a chance to act but there where no
breakpoints or ... so the debugger pops up the message. The worst that
should happen in non debug mode is that the application will go non
responsive.

Lloyd Sheen
 
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