How to convert a Byte() to an IntPtr in VB

**Serge BRIC** · Oct 16 '06, 08:15 AM

RE: How to convert a Byte() to an IntPtr in VB

Sorry for this double message (I thought the previous one had failed).

**TDC** · Oct 16 '06, 01:15 PM

Re: How to convert a Byte() to an IntPtr in VB

The Marshal class (in System.Runtime. Interop) has mothods to convert
(copy actually) to and from unmanaged memory. If you browse the
methods there, you'll quickly find what you are looking for in response
to this and your other similar posted question.

Tom

Serge BRIC wrote:

My application, written in .NET VB, tries to get a communication port handle
from a TAPI object with this code:
>
Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")
>
The vFileHandle is supposed to be a file handle (an IntPtr, I suppose). How
can I convert this Byte() in this IntPtr ?

**Serge BRIC** · Oct 17 '06, 10:35 AM

Re: How to convert a Byte() to an IntPtr in VB

I have obtained the TAPI3 file handle with VB and C++ code, like this:

Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")
Dim iFileHandle As IntPtr
iFileHandle = BytePtr2Handle( vFileHandle)

The C++ BytePtr2Handle( ) is :

__declspec(dlle xport) HANDLE BytePtr2Handle( BYTE* p)
{
return *((LPHANDLE)p);
}

I'm certain it could be done, in a simpler way, in VB (without C++ code) but
I don't know how.

"TDC" wrote:

The Marshal class (in System.Runtime. Interop) has mothods to convert
(copy actually) to and from unmanaged memory. If you browse the
methods there, you'll quickly find what you are looking for in response
to this and your other similar posted question.
>
Tom
>
>
Serge BRIC wrote:

My application, written in .NET VB, tries to get a communication port handle
from a TAPI object with this code:

Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")

The vFileHandle is supposed to be a file handle (an IntPtr, I suppose). How
can I convert this Byte() in this IntPtr ?

>
>

**Jay B. Harlow** · Oct 17 '06, 11:35 AM

Re: How to convert a Byte() to an IntPtr in VB

Serge,

Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")

Why is GetIDAsVariant returning a Byte()? It appears that it really should
return a COM VARIANT, in the .NET world COM Variants are exposed as
System.Object.

As TDC suggested: System.Runtime. Interop.Marshal is your friend here. It has
methods to marshal (convert/translate) between the COM/C++ (unmanaged) world
& the .NET (managed) world... However it helps to define the methods &
interfaces that you use first, as P/Invoke (how you define the method) is
your first "defense" on converting unmanaged types.

FWIW The name GetIDAsVariant, suggests it returns a COM Variant, a Google
search reinforces this notion. I normally check www.pinvoke.net for the
correct definitions of unmanaged interfaces & methods that I want to use in
the managed world.

--
Hope this helps
Jay B. Harlow
..NET Application Architect, Enthusiast, & Evangelist
T.S. Bradley - http://www.tsbradley.net

"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
news:0BE821CE-C60D-4438-BAAF-5E876666E541@mi crosoft.com...

My application, written in .NET VB, tries to get a communication port
handle
from a TAPI object with this code:
>
Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")
>
The vFileHandle is supposed to be a file handle (an IntPtr, I suppose).
How
can I convert this Byte() in this IntPtr ?

**Serge BRIC** · Oct 17 '06, 03:35 PM

Re: How to convert a Byte() to an IntPtr in VB

Jay,

You're right, GetIDAsVariant( ) returns a COM Variant in C++ exposed as a
System.Object in .NET. It appears that the type of this .NET object is
System.Array and that the type of each item of this array is a byte. This is
why I was trying to interpret it as an array of bytes (Byte()).

I found on the TAPI newsgroup that the correct way of getting the com port
handle in C++ from a ITLegacyCallMed iaControl object (TAPI3 object) was
something like :

BSTR bstrComm = ::SysAllocStrin g(L"comm/datamodem");
BYTE *pDeviceID;
DWORD dwSize;
ITLegacyCallMed iaControl *pCallMediaCont rol;
...
HRESULT hr = pCallMediaContr ol->GetID(bstrComm , &dwSize, &pDeviceID);
HANDLE handle = *((LPHANDLE)pDe viceID);

So, in VB, it is:

Dim appel As ITLegacyCallMed iaControl2
...
Dim obj As Object = callMediaContro l.GetIDAsVarian t("comm/datamodem")
Dim handle As IntPtr = Marshal.ReadInt Ptr(obj, 0)

Thanks for your help.

"Jay B. Harlow" wrote:

Serge,

Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")

Why is GetIDAsVariant returning a Byte()? It appears that it really should
return a COM VARIANT, in the .NET world COM Variants are exposed as
System.Object.
>
As TDC suggested: System.Runtime. Interop.Marshal is your friend here. It has
methods to marshal (convert/translate) between the COM/C++ (unmanaged) world
& the .NET (managed) world... However it helps to define the methods &
interfaces that you use first, as P/Invoke (how you define the method) is
your first "defense" on converting unmanaged types.
>
>
FWIW The name GetIDAsVariant, suggests it returns a COM Variant, a Google
search reinforces this notion. I normally check www.pinvoke.net for the
correct definitions of unmanaged interfaces & methods that I want to use in
the managed world.
>
--
Hope this helps
Jay B. Harlow
.NET Application Architect, Enthusiast, & Evangelist
T.S. Bradley - http://www.tsbradley.net
>
>
"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
news:0BE821CE-C60D-4438-BAAF-5E876666E541@mi crosoft.com...

My application, written in .NET VB, tries to get a communication port
handle
from a TAPI object with this code:

Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")

The vFileHandle is supposed to be a file handle (an IntPtr, I suppose).
How
can I convert this Byte() in this IntPtr ?

>

**Jay B. Harlow** · Oct 17 '06, 09:35 PM

Re: How to convert a Byte() to an IntPtr in VB

Serge,
I would not expect a Handle to be returned as a Byte().

I would expect a Handle to be returned as an Integer...

How is your ITLegacyCallMed iaControl2 defined?

--
Hope this helps
Jay B. Harlow
..NET Application Architect, Enthusiast, & Evangelist
T.S. Bradley - http://www.tsbradley.net

"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
news:BAEF8A64-1BDF-4D86-9340-B2B5A4E975A9@mi crosoft.com...

Jay,
>
You're right, GetIDAsVariant( ) returns a COM Variant in C++ exposed as a
System.Object in .NET. It appears that the type of this .NET object is
System.Array and that the type of each item of this array is a byte. This
is
why I was trying to interpret it as an array of bytes (Byte()).
>
I found on the TAPI newsgroup that the correct way of getting the com port
handle in C++ from a ITLegacyCallMed iaControl object (TAPI3 object) was
something like :
>
BSTR bstrComm = ::SysAllocStrin g(L"comm/datamodem");
BYTE *pDeviceID;
DWORD dwSize;
ITLegacyCallMed iaControl *pCallMediaCont rol;
...
HRESULT hr = pCallMediaContr ol->GetID(bstrComm , &dwSize, &pDeviceID);
HANDLE handle = *((LPHANDLE)pDe viceID);
>
So, in VB, it is:
>
Dim appel As ITLegacyCallMed iaControl2
...
Dim obj As Object =
callMediaContro l.GetIDAsVarian t("comm/datamodem")
Dim handle As IntPtr = Marshal.ReadInt Ptr(obj, 0)
>
Thanks for your help.
>
>
"Jay B. Harlow" wrote:
>

>Serge,

Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")

>Why is GetIDAsVariant returning a Byte()? It appears that it really
>should
>return a COM VARIANT, in the .NET world COM Variants are exposed as
>System.Objec t.
>>
>As TDC suggested: System.Runtime. Interop.Marshal is your friend here. It
>has
>methods to marshal (convert/translate) between the COM/C++ (unmanaged)
>world
>& the .NET (managed) world... However it helps to define the methods &
>interfaces that you use first, as P/Invoke (how you define the method) is
>your first "defense" on converting unmanaged types.
>>
>>
>FWIW The name GetIDAsVariant, suggests it returns a COM Variant, a Google
>search reinforces this notion. I normally check www.pinvoke.net for the
>correct definitions of unmanaged interfaces & methods that I want to use
>in
>the managed world.
>>
>--
>Hope this helps
>Jay B. Harlow
>.NET Application Architect, Enthusiast, & Evangelist
>T.S. Bradley - http://www.tsbradley.net
>>
>>
>"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
>news:0BE821C E-C60D-4438-BAAF-5E876666E541@mi crosoft.com...

My application, written in .NET VB, tries to get a communication port
handle
from a TAPI object with this code:
>
Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")
>
The vFileHandle is supposed to be a file handle (an IntPtr, I suppose).
How
can I convert this Byte() in this IntPtr ?

>>

**Serge BRIC** · Oct 18 '06, 06:35 AM

Re: How to convert a Byte() to an IntPtr in VB

Jay,

ITLegacyCallMed iaControl2 is an extension of the ITLegacyCallMed iaControl
which is one of the interfaces of the TAPI3 call object created when an
address connects to another one. GetIDAsVariant( ) is a method of the
ITLegacyCallMed iaControl2 interface (in C++, it is
ITLegacyCallMed iaControl::GetI D()).

I don't understand either why the return of
ITLegacyCallMed iaControl2::Get IDAsVariant() is so opaque. It seems like it's
a low level function.

Here are some pieces of the related code :

Dim tapi As ITTAPI
Dim adresse As ITAddress
Dim appel As ITBasicCallCont rol
Dim telephoneNumber as String

'Create the tapi object.
tapi = New TAPI
'Call Initialize before calling any other TAPI function.
Call tapi.Initialize ()
...
'adresse is one of the tapi.Addresses
...
'create a data call to a phone number
appel = adresse.CreateC all(telephoneNu mber,
TapiConstants.L INEADDRESSTYPE_ PHONENUMBER,
TapiConstants.T APIMEDIATYPE_DA TAMODEM)
appel.Connect(F alse)
...
'gets the TAPI3 comm port name
Dim portName As Byte() =
appel.GetIDAsVa riant("comm/datamodem/portname")
'portName has to be converted to a String, each byte becoming a Char
of the String

'gets the TAPI3 comm port handle
Dim obj As Object = appel.GetIDAsVa riant("comm/datamodem")
Dim hPort As IntPtr = Marshal.ReadInt Ptr(obj, 0)

'now, you can use this handle in Win32 WriteFile(), ReadFile() calls
...

"Jay B. Harlow" wrote:

Serge,
I would not expect a Handle to be returned as a Byte().
>
I would expect a Handle to be returned as an Integer...
>
How is your ITLegacyCallMed iaControl2 defined?
>
>
--
Hope this helps
Jay B. Harlow
.NET Application Architect, Enthusiast, & Evangelist
T.S. Bradley - http://www.tsbradley.net
>
>
"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
news:BAEF8A64-1BDF-4D86-9340-B2B5A4E975A9@mi crosoft.com...

Jay,

You're right, GetIDAsVariant( ) returns a COM Variant in C++ exposed as a
System.Object in .NET. It appears that the type of this .NET object is
System.Array and that the type of each item of this array is a byte. This
is
why I was trying to interpret it as an array of bytes (Byte()).

I found on the TAPI newsgroup that the correct way of getting the com port
handle in C++ from a ITLegacyCallMed iaControl object (TAPI3 object) was
something like :

BSTR bstrComm = ::SysAllocStrin g(L"comm/datamodem");
BYTE *pDeviceID;
DWORD dwSize;
ITLegacyCallMed iaControl *pCallMediaCont rol;
...
HRESULT hr = pCallMediaContr ol->GetID(bstrComm , &dwSize, &pDeviceID);
HANDLE handle = *((LPHANDLE)pDe viceID);

So, in VB, it is:

Dim appel As ITLegacyCallMed iaControl2
...
Dim obj As Object =
callMediaContro l.GetIDAsVarian t("comm/datamodem")
Dim handle As IntPtr = Marshal.ReadInt Ptr(obj, 0)

Thanks for your help.

"Jay B. Harlow" wrote:

Serge,
Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")
Why is GetIDAsVariant returning a Byte()? It appears that it really
should
return a COM VARIANT, in the .NET world COM Variants are exposed as
System.Object.
>
As TDC suggested: System.Runtime. Interop.Marshal is your friend here. It
has
methods to marshal (convert/translate) between the COM/C++ (unmanaged)
world
& the .NET (managed) world... However it helps to define the methods &
interfaces that you use first, as P/Invoke (how you define the method) is
your first "defense" on converting unmanaged types.
>
>
FWIW The name GetIDAsVariant, suggests it returns a COM Variant, a Google
search reinforces this notion. I normally check www.pinvoke.net for the
correct definitions of unmanaged interfaces & methods that I want to use
in
the managed world.
>
--
Hope this helps
Jay B. Harlow
.NET Application Architect, Enthusiast, & Evangelist
T.S. Bradley - http://www.tsbradley.net
>
>
"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
news:0BE821CE-C60D-4438-BAAF-5E876666E541@mi crosoft.com...
My application, written in .NET VB, tries to get a communication port
handle
from a TAPI object with this code:

Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")

The vFileHandle is supposed to be a file handle (an IntPtr, I suppose).
How
can I convert this Byte() in this IntPtr ?
>

>

**Jay B. Harlow** · Oct 18 '06, 12:25 PM

Re: How to convert a Byte() to an IntPtr in VB

Serge,
I know what it is. :-|

I wanted to see your VB.NET definition of ITLegacyCallMed iaControl2!

I wanted to make sure you had that defined correctly...

--
Hope this helps
Jay B. Harlow
..NET Application Architect, Enthusiast, & Evangelist
T.S. Bradley - http://www.tsbradley.net

"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
news:C098F5A6-1C85-4665-8A0C-ECC323E70783@mi crosoft.com...

Jay,
>
ITLegacyCallMed iaControl2 is an extension of the ITLegacyCallMed iaControl
which is one of the interfaces of the TAPI3 call object created when an
address connects to another one. GetIDAsVariant( ) is a method of the
ITLegacyCallMed iaControl2 interface (in C++, it is
ITLegacyCallMed iaControl::GetI D()).
>
I don't understand either why the return of
ITLegacyCallMed iaControl2::Get IDAsVariant() is so opaque. It seems like
it's
a low level function.
>
Here are some pieces of the related code :
>
Dim tapi As ITTAPI
Dim adresse As ITAddress
Dim appel As ITBasicCallCont rol
Dim telephoneNumber as String
>
'Create the tapi object.
tapi = New TAPI
'Call Initialize before calling any other TAPI function.
Call tapi.Initialize ()
...
'adresse is one of the tapi.Addresses
...
'create a data call to a phone number
appel = adresse.CreateC all(telephoneNu mber,
TapiConstants.L INEADDRESSTYPE_ PHONENUMBER,
TapiConstants.T APIMEDIATYPE_DA TAMODEM)
appel.Connect(F alse)
...
'gets the TAPI3 comm port name
Dim portName As Byte() =
appel.GetIDAsVa riant("comm/datamodem/portname")
'portName has to be converted to a String, each byte becoming a
Char
of the String
>
'gets the TAPI3 comm port handle
Dim obj As Object = appel.GetIDAsVa riant("comm/datamodem")
Dim hPort As IntPtr = Marshal.ReadInt Ptr(obj, 0)
>
'now, you can use this handle in Win32 WriteFile(), ReadFile()
calls
...
>
"Jay B. Harlow" wrote:
>

>Serge,
>I would not expect a Handle to be returned as a Byte().
>>
>I would expect a Handle to be returned as an Integer...
>>
>How is your ITLegacyCallMed iaControl2 defined?
>>
>>
>--
>Hope this helps
>Jay B. Harlow
>.NET Application Architect, Enthusiast, & Evangelist
>T.S. Bradley - http://www.tsbradley.net
>>
>>
>"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
>news:BAEF8A6 4-1BDF-4D86-9340-B2B5A4E975A9@mi crosoft.com...

Jay,
>
You're right, GetIDAsVariant( ) returns a COM Variant in C++ exposed as
a
System.Object in .NET. It appears that the type of this .NET object is
System.Array and that the type of each item of this array is a byte.
This
is
why I was trying to interpret it as an array of bytes (Byte()).
>
I found on the TAPI newsgroup that the correct way of getting the com
port
handle in C++ from a ITLegacyCallMed iaControl object (TAPI3 object) was
something like :
>
BSTR bstrComm = ::SysAllocStrin g(L"comm/datamodem");
BYTE *pDeviceID;
DWORD dwSize;
ITLegacyCallMed iaControl *pCallMediaCont rol;
...
HRESULT hr = pCallMediaContr ol->GetID(bstrComm , &dwSize, &pDeviceID);
HANDLE handle = *((LPHANDLE)pDe viceID);
>
So, in VB, it is:
>
Dim appel As ITLegacyCallMed iaControl2
...
Dim obj As Object =
callMediaContro l.GetIDAsVarian t("comm/datamodem")
Dim handle As IntPtr = Marshal.ReadInt Ptr(obj, 0)
>
Thanks for your help.
>
>
"Jay B. Harlow" wrote:
>
>Serge,
Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")
>Why is GetIDAsVariant returning a Byte()? It appears that it really
>should
>return a COM VARIANT, in the .NET world COM Variants are exposed as
>System.Objec t.
>>
>As TDC suggested: System.Runtime. Interop.Marshal is your friend here.
>It
>has
>methods to marshal (convert/translate) between the COM/C++ (unmanaged)
>world
>& the .NET (managed) world... However it helps to define the methods &
>interfaces that you use first, as P/Invoke (how you define the method)
>is
>your first "defense" on converting unmanaged types.
>>
>>
>FWIW The name GetIDAsVariant, suggests it returns a COM Variant, a
>Google
>search reinforces this notion. I normally check www.pinvoke.net for
>the
>correct definitions of unmanaged interfaces & methods that I want to
>use
>in
>the managed world.
>>
>--
>Hope this helps
>Jay B. Harlow
>.NET Application Architect, Enthusiast, & Evangelist
>T.S. Bradley - http://www.tsbradley.net
>>
>>
>"Serge BRIC" <SergeBRIC@disc ussions.microso ft.comwrote in message
>news:0BE821C E-C60D-4438-BAAF-5E876666E541@mi crosoft.com...
My application, written in .NET VB, tries to get a communication
port
handle
from a TAPI object with this code:
>
Dim vFileHandle As Byte() = appel.GetIDAsVa riant("comm/datamodem")
>
The vFileHandle is supposed to be a file handle (an IntPtr, I
suppose).
How
can I convert this Byte() in this IntPtr ?
>>

>>

How to convert a Byte() to an IntPtr in VB

How to convert a Byte() to an IntPtr in VB

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