.NET, COM and PB

[Philippe Monteil]

Hello,

I recommend the following article from the August issue of MSDN:
http://msdn.microsoft.com/msdnmag/is...op/Interop.asp
detailing how COM clients/servers will be able to interact with
.NET classes/applications.

From what I understand, a COM client application will be able to
call a .NET class as if it was a COM component. Also a form
capable of hosting ActiveX controls (OCXs) will also be able to
host .NET Controls at no additional cost.

Symetrically, a .NET application will be able to call COM components
as if they were native .NET classes, and .NET forms will be able
to host OCXs.

Making PB capable of creating COM components and OCXs would suffice
to make it and excellent addon for the .NET platform, thanks to its
inner qualities (size and speed).

Making PB able to access COM components would give its developers
an instant access to key existing (COM components) and future (.NET
classes) software resources.

Philippe Monteil
JAZZAge Software



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[Lance Edmonds]

Thanks for the feedback Philippe! We'll add another tick to the COM entry in the wish list.

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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Philippe Monteil]

<<Thanks for the feedback Philippe! We'll add another tick to the COM entry in the wish list.
You are welcome

Some other topics, like SOAP Web Services, will have a deep impact
on software development and would therefore be worth mentioning as well.

Imagine you can invoke the functionalities exposed by a Java class
running on a Linux box from within your PB application, or that you can
make your PB DLLs available to a Java application running on a Mac
at no additional development cost...

The multiplateform capabilities of a development tool become much less
important than its ability to connect to and be accessed from Web services
through a universal middleware like SOAP.

Philippe



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[Francis Beaulieu]

Bonjour Phil!

Soap is just a protocol in XML that you can do (or reproduce
the functionality) without an ActiveX on the client side. You
can make a Dll in PB to read the XML (a hard work like the PB
programmers love it ;- ). Voilà!

Regards



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Francis Beaulieu
FrabLaser Softwares

[Philippe Monteil]

Bonjour Francis,

<<Soap is just a protocol in XML that you can do (or reproduce
<<the functionality) without an ActiveX on the client side. You
<<can make a Dll in PB to read the XML (a hard work like the PB
<<programmers love it ;- ). Voilà!
You are right, SOAP is 'only' a spec describing how object invocations
should be packed into XML documents and then sent through HTTP
requests. It is therefore already possible to invoke SOAP objects
in PB/DLL by hand coding the various and rather touchy steps involved,
but IMO a much higher level of integration in PB is required to make
Web services effectively usable in real world developments.

Web services describe their signature and their location (the address of the
web server to send the SOAP requests to) in WSDL compliant XML documents.
Those WSDL descriptions make possible to automatically generate the code
wrapping a Web Service and make it look like a local objet. The free
MS SOAP SDK 2.0 goes even further in that it maps a web service as a
COM Automation object without needing to generate any connection code:
everything is done dynamically, at runtime, in 2 lines of code.

A typical WebService invocation using the MS SOAP SDK looks like:

Dim soapclient As Object
' Create an instance of the MSSOAP.SoapClient COM component
' provided by the SOAP SDK
set soapclient = CreateObject("MSSOAP.SoapClient")
' connect to the soap client to a webservice, given the URL of its WSDL description
Call soapclient.mssoapinit("http://www.webservice.com/Calculator.wsdl", "", "")
' at this point, the soapclient component fully impersonates the
' connected web service, which then appears as an ordinary COM component
' exposing the same methods as the wrapped webservice.
' call the web service methods
result=soapclient.AddNumbers(2,3)
result=soapclient.SubtractNumbers(3,2)

A full support for Automation components would make possible to do
the same thing in PB.

You will find a list of some publicly available web services at:
http://xmethods.com/

The following web site is dedicated to web services and offers
a great deal of information on that topic:
http://www.webservices.org

Philippe




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[Brent Eldstrom]

If anyone wants to read an opinion of .NET by a well respected member of the open source community go here:
http://www.oreillynet.com/pub/a/dotn.../09/icaza.html

Miguel de Icaza is a leader of the GNOME project and his opinions carry alot of weight.

Brent...

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[Philippe Monteil]

Very interesting, thanks! I would like to add that WebServices
are plateform neutral: they can be built and used with or
without .NET.

Philippe



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