Consider the following simple classes/interfaces defined below. When the
derived class raises the events, on which thread is the event code run? Do
I need to do anything to catch the events in my main app? What threading
issues do I have if several of these fileproc classes are instantiated and
run at the same time?
'*** BEGIN CODE
Public Interface IFileProc
ReadOnly Property FileMask() As String
Function Process(ByVal filename As String) As Integer
Event BeginFileProc(B yVal filename As String)
Event EndFileProc(ByV al filename As String)
Event ProcProgress(By Val filename As String, ByVal percent As Integer)
End Interface
Public MustInherit Class ThreadWrapperBa se
Public ReadOnly WorkThread As System.Threadin g.Thread
Public Sub New()
Me.WorkThread = New System.Threadin g.Thread(Addres sOf Me.StartTask)
End Sub
Public Overridable Sub Start()
Me.WorkThread.S tart()
End Sub
Public Overridable Sub [Stop]()
Me.WorkThread.A bort()
End Sub
Private _IsCompleted As Boolean
Public ReadOnly Property IsCompleted() As Boolean
Get
Return _IsCompleted
End Get
End Property
Private Sub StartTask()
_IsCompleted = False
DoTask()
_IsCompleted = True
End Sub
Protected MustOverride Sub DoTask()
End Class
Public Class FileProcClass()
Inherits ThreadWrapperBa se
Implement IFileProc
Private _FileToProcess As String
'This is the sub where the file processing actually takes place
Protected Overrides Sub DoTask()
RaiseEvent BeginFileProc(_ FileToProcess)
'Process file here
RaiseEvent EndFileProc(_Fi leToProcess)
End Sub
Public Function Process(...) As Integer Implements IFileProc.Proce ss
_FileToProcess = filename
Start()
End Function
End Class
'*** END CODE
--
Chris
dunawayc[AT]sbcglobal_lunch meat_[DOT]net
To send me an E-mail, remove the "[", "]", underscores ,lunchmeat, and
replace certain words in my E-Mail address. 3 2548
The event is raised on the thread that called it. And executed on the
thread that called it (regardless of where the sink was created).
The easiest way I've seen to do this is to create an instance of the Control
class on the thread you want to execute on.
I.e. you want a thread to execute on your main thread from another, before
creating the other thread, create an instance of the Control class (watch
for getting a Handle, sometimes that can cause a problem.) on that main
thread.
Then, when you receive an event, use the Controls Invoke method to invoke
whatever method it is you want on the main thread (the *true* event handler
if you will). This invokes the method on the thread it was created on,
doing all the dirty work of crossing over to the main thread from the
secondary thread. And there you go.
Verify by using the Thread.CurrentT hread.HashCode. . Or name your threads...
Might have to watch for deadlock though, as your second thread will
effectivly be waiting on your main thread to complete the task before it
continues on.
HTH,
CJ
"Chris Dunaway" <"dunawayc[[at]_lunchmeat_sbcg lobal[dot]]net"> wrote in
message news:1c******** *************** ********@40tude .net... Consider the following simple classes/interfaces defined below. When the derived class raises the events, on which thread is the event code run?
Do I need to do anything to catch the events in my main app? What threading issues do I have if several of these fileproc classes are instantiated and run at the same time?
'*** BEGIN CODE Public Interface IFileProc ReadOnly Property FileMask() As String Function Process(ByVal filename As String) As Integer Event BeginFileProc(B yVal filename As String) Event EndFileProc(ByV al filename As String) Event ProcProgress(By Val filename As String, ByVal percent As Integer) End Interface
Public MustInherit Class ThreadWrapperBa se Public ReadOnly WorkThread As System.Threadin g.Thread
Public Sub New() Me.WorkThread = New System.Threadin g.Thread(Addres sOf
Me.StartTask) End Sub
Public Overridable Sub Start() Me.WorkThread.S tart() End Sub
Public Overridable Sub [Stop]() Me.WorkThread.A bort() End Sub
Private _IsCompleted As Boolean Public ReadOnly Property IsCompleted() As Boolean Get Return _IsCompleted End Get End Property
Private Sub StartTask() _IsCompleted = False DoTask() _IsCompleted = True End Sub
Protected MustOverride Sub DoTask() End Class
Public Class FileProcClass() Inherits ThreadWrapperBa se Implement IFileProc
Private _FileToProcess As String
'This is the sub where the file processing actually takes place Protected Overrides Sub DoTask() RaiseEvent BeginFileProc(_ FileToProcess) 'Process file here RaiseEvent EndFileProc(_Fi leToProcess) End Sub
Public Function Process(...) As Integer Implements IFileProc.Proce ss _FileToProcess = filename Start() End Function End Class '*** END CODE
-- Chris
dunawayc[AT]sbcglobal_lunch meat_[DOT]net
To send me an E-mail, remove the "[", "]", underscores ,lunchmeat, and replace certain words in my E-Mail address.
On Mon, 4 Oct 2004 13:35:38 -0500, CJ Taylor wrote: The event is raised on the thread that called it. And executed on the thread that called it (regardless of where the sink was created).
The easiest way I've seen to do this is to create an instance of the Control class on the thread you want to execute on.
I.e. you want a thread to execute on your main thread from another, before creating the other thread, create an instance of the Control class (watch for getting a Handle, sometimes that can cause a problem.) on that main thread.
Then, when you receive an event, use the Controls Invoke method to invoke whatever method it is you want on the main thread (the *true* event handler if you will). This invokes the method on the thread it was created on, doing all the dirty work of crossing over to the main thread from the secondary thread. And there you go.
Verify by using the Thread.CurrentT hread.HashCode. . Or name your threads...
Might have to watch for deadlock though, as your second thread will effectivly be waiting on your main thread to complete the task before it continues on.
HTH, CJ
"Chris Dunaway" <"dunawayc[[at]_lunchmeat_sbcg lobal[dot]]net"> wrote in message news:1c******** *************** ********@40tude .net... Consider the following simple classes/interfaces defined below. When the derived class raises the events, on which thread is the event code run? Do I need to do anything to catch the events in my main app? What threading issues do I have if several of these fileproc classes are instantiated and run at the same time?
'*** BEGIN CODE Public Interface IFileProc ReadOnly Property FileMask() As String Function Process(ByVal filename As String) As Integer Event BeginFileProc(B yVal filename As String) Event EndFileProc(ByV al filename As String) Event ProcProgress(By Val filename As String, ByVal percent As Integer) End Interface
Public MustInherit Class ThreadWrapperBa se Public ReadOnly WorkThread As System.Threadin g.Thread
Public Sub New() Me.WorkThread = New System.Threadin g.Thread(Addres sOf Me.StartTask) End Sub
Public Overridable Sub Start() Me.WorkThread.S tart() End Sub
Public Overridable Sub [Stop]() Me.WorkThread.A bort() End Sub
Private _IsCompleted As Boolean Public ReadOnly Property IsCompleted() As Boolean Get Return _IsCompleted End Get End Property
Private Sub StartTask() _IsCompleted = False DoTask() _IsCompleted = True End Sub
Protected MustOverride Sub DoTask() End Class
Public Class FileProcClass() Inherits ThreadWrapperBa se Implement IFileProc
Private _FileToProcess As String
'This is the sub where the file processing actually takes place Protected Overrides Sub DoTask() RaiseEvent BeginFileProc(_ FileToProcess) 'Process file here RaiseEvent EndFileProc(_Fi leToProcess) End Sub
Public Function Process(...) As Integer Implements IFileProc.Proce ss _FileToProcess = filename Start() End Function End Class '*** END CODE
-- Chris
dunawayc[AT]sbcglobal_lunch meat_[DOT]net
To send me an E-mail, remove the "[", "]", underscores ,lunchmeat, and replace certain words in my E-Mail address.
Thanks for the response. I think you have helped me.
--
Chris
dunawayc[AT]sbcglobal_lunch meat_[DOT]net
To send me an E-mail, remove the "[", "]", underscores ,lunchmeat, and
replace certain words in my E-Mail address.
Not a problem... happy to help.
"Chris Dunaway" <"dunawayc[[at]_lunchmeat_sbcg lobal[dot]]net"> wrote in
message news:lg******** *************** *****@40tude.ne t... On Mon, 4 Oct 2004 13:35:38 -0500, CJ Taylor wrote:
The event is raised on the thread that called it. And executed on the thread that called it (regardless of where the sink was created).
The easiest way I've seen to do this is to create an instance of the Control class on the thread you want to execute on.
I.e. you want a thread to execute on your main thread from another, before creating the other thread, create an instance of the Control class (watch for getting a Handle, sometimes that can cause a problem.) on that main thread.
Then, when you receive an event, use the Controls Invoke method to invoke whatever method it is you want on the main thread (the *true* event handler if you will). This invokes the method on the thread it was created on, doing all the dirty work of crossing over to the main thread from the secondary thread. And there you go.
Verify by using the Thread.CurrentT hread.HashCode. . Or name your threads...
Might have to watch for deadlock though, as your second thread will effectivly be waiting on your main thread to complete the task before it continues on.
HTH, CJ
"Chris Dunaway" <"dunawayc[[at]_lunchmeat_sbcg lobal[dot]]net"> wrote in message news:1c******** *************** ********@40tude .net... Consider the following simple classes/interfaces defined below. When the derived class raises the events, on which thread is the event code run? Do I need to do anything to catch the events in my main app? What threading issues do I have if several of these fileproc classes are instantiated and run at the same time?
'*** BEGIN CODE Public Interface IFileProc ReadOnly Property FileMask() As String Function Process(ByVal filename As String) As Integer Event BeginFileProc(B yVal filename As String) Event EndFileProc(ByV al filename As String) Event ProcProgress(By Val filename As String, ByVal percent As Integer) End Interface
Public MustInherit Class ThreadWrapperBa se Public ReadOnly WorkThread As System.Threadin g.Thread
Public Sub New() Me.WorkThread = New System.Threadin g.Thread(Addres sOf Me.StartTask) End Sub
Public Overridable Sub Start() Me.WorkThread.S tart() End Sub
Public Overridable Sub [Stop]() Me.WorkThread.A bort() End Sub
Private _IsCompleted As Boolean Public ReadOnly Property IsCompleted() As Boolean Get Return _IsCompleted End Get End Property
Private Sub StartTask() _IsCompleted = False DoTask() _IsCompleted = True End Sub
Protected MustOverride Sub DoTask() End Class
Public Class FileProcClass() Inherits ThreadWrapperBa se Implement IFileProc
Private _FileToProcess As String
'This is the sub where the file processing actually takes place Protected Overrides Sub DoTask() RaiseEvent BeginFileProc(_ FileToProcess) 'Process file here RaiseEvent EndFileProc(_Fi leToProcess) End Sub
Public Function Process(...) As Integer Implements IFileProc.Proce ss _FileToProcess = filename Start() End Function End Class '*** END CODE
-- Chris
dunawayc[AT]sbcglobal_lunch meat_[DOT]net
To send me an E-mail, remove the "[", "]", underscores ,lunchmeat, and replace certain words in my E-Mail address.
Thanks for the response. I think you have helped me. -- Chris
dunawayc[AT]sbcglobal_lunch meat_[DOT]net
To send me an E-mail, remove the "[", "]", underscores ,lunchmeat, and replace certain words in my E-Mail address. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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