hi
New to delegates, trying to figure out how to use a
delegate to fix a bug after upgrading code from VB6 to
VB.NET

I have the following callback proc:
' in vb 6.0

###############################################################################
Public Sub LineCallbackProc(ByVal hDevice As Long, _
ByVal dwMsg As Long, _
ByVal dwCallbackInstance As Long, _
ByVal dwParam1 As Long, _
ByVal dwParam2 As Long, _
ByVal dwParam3 As Long)
'the callbackInstance parameter contains a pointer to the
CvbTAPILine class
'this sub just routes all callbacks back to the class for handling
there
Dim PassedObj As CvbTAPILine
Dim objTemp As CvbTAPILine
Debug.Print "LineCALLBACK : dwCallbackInst = " &
dwCallbackInstance
If dwCallbackInstance <> 0 Then
'turn pointer into illegal, uncounted reference
'Debug.Print "step #1"
CopyMemory objTemp, dwCallbackInstance, 4
'Assign to legal reference
'Debug.Print "step #2"
Set PassedObj = objTemp
'Destroy the illegal reference
'Debug.Print "step #3"
CopyMemory objTemp, 0&, 4
'use the interface to call back to the class
'Debug.Print "step #4"
PassedObj.LineProcHandler hDevice, dwMsg, dwParam1, dwParam2,
dwParam3
'Debug.Print "step #5"


End If

End Sub
###############################################################################

rc = lineInitializeEx(m_hLineApp, App.hInstance, AddressOf _
LineCallbackProc, App.Title, _
m_numLines, m_HiAPI, lip)
###############################################################################


When i converted this in vb.net i get an errors stating that

'AddressOf' expression cannot be converted to 'Integer' because
'Integer' is not a delegate type.

i have made some study on this .
1.) first we have to create a delegate object on the callback function
then
2.) we have to put the correct signature and bla.. bla
i have tried many things but it seems doesn't help me
if any body can help me please provide me the code , its urgent

TIA

Hi,

Maybe this will help
http://www.elitevb.com/content/01,0075,01/04.aspx

Ken
---------------
"suria`" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> hi
> New to delegates, trying to figure out how to use a
> delegate to fix a bug after upgrading code from VB6 to
> VB.NET
>
> I have the following callback proc:
> ' in vb 6.0
>
>
############################################################################
###
> Public Sub LineCallbackProc(ByVal hDevice As Long, _
> ByVal dwMsg As Long, _
> ByVal dwCallbackInstance As Long, _
> ByVal dwParam1 As Long, _
> ByVal dwParam2 As Long, _
> ByVal dwParam3 As Long)
> 'the callbackInstance parameter contains a pointer to the
> CvbTAPILine class
> 'this sub just routes all callbacks back to the class for handling
> there
> Dim PassedObj As CvbTAPILine
> Dim objTemp As CvbTAPILine
> Debug.Print "LineCALLBACK : dwCallbackInst = " &
> dwCallbackInstance
> If dwCallbackInstance <> 0 Then
> 'turn pointer into illegal, uncounted reference
> 'Debug.Print "step #1"
> CopyMemory objTemp, dwCallbackInstance, 4
> 'Assign to legal reference
> 'Debug.Print "step #2"
> Set PassedObj = objTemp
> 'Destroy the illegal reference
> 'Debug.Print "step #3"
> CopyMemory objTemp, 0&, 4
> 'use the interface to call back to the class
> 'Debug.Print "step #4"
> PassedObj.LineProcHandler hDevice, dwMsg, dwParam1, dwParam2,
> dwParam3
> 'Debug.Print "step #5"
>
>
> End If
>
> End Sub
>
############################################################################
###
>
> rc = lineInitializeEx(m_hLineApp, App.hInstance, AddressOf _
> LineCallbackProc, App.Title, _
> m_numLines, m_HiAPI, lip)
>
############################################################################
###
>
>
> When i converted this in vb.net i get an errors stating that
>
> 'AddressOf' expression cannot be converted to 'Integer' because
> 'Integer' is not a delegate type.
>
> i have made some study on this .
> 1.) first we have to create a delegate object on the callback function
> then
> 2.) we have to put the correct signature and bla.. bla
> i have tried many things but it seems doesn't help me
> if any body can help me please provide me the code , its urgent
>
> TIA

thanks for your link
i have solve the problem
thanks again