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 From: Eric den Doop
  Where is Eric den Doop?
 Eric den Doop
  Where is ERNESTO PAEZ?
 Florida - United States
Subject: RE: how to create my own toolbars or add some of them to my appl
Thread ID: 480 Message ID: 486 # Views: 5 # Ratings: 0
Version: Unknown Category: General VFP Topics
Date: Thursday, May 31, 2001 4:44:04 PM         

> Thank Eric i am going to try this, this is the beginning thank a lot for your help we need people like you to mak evfp to keep going and let us learn.
> do you recommend me anything else to learn more about vfp in my case 6.0 ah by the way i dont know yet what is COM or what for it could be use, is this some kind of third party software or is it a command what can i do with the COM ,
> SORRY for my ignorance but i need to learn about may be this help me out to create better stuffs
> thank you

Hi there

Things i recommend you to learn? Well that is a very difficult question. A man should know what a man has to know and wants to know. That is: if you are interested in rabbits, then go learn about rabbits. If you like astronomy, then learn about astronomy. If you want to learn VFP instead of Access :) then go and learn VFP. To extend your VFP knowledge, you must know the basics: what is a form, what is a table, what is a toolbar, what is a button etc etc etc. If you dont know them, then you can better stop right away. What i'm trying to say is that if you think you're up to something new, for example Foxpro web apps or web sites like Foxite which is my first VFP driven web site, then go for it. Make sure you collect enough information and samples and that is something that is quite easy to do. In the early days we had to go to the library to get some books, but now we have Internet and with the Internet you can search the whole world and beyond (remember that lovely little car on Mars?).

That brings me to your question about COM. COM stands for Component Object Model. What it is? To be short: it is an object that is available to other programs, no matter the programming language it was written in. For example the Foxite Web Engine is a VFP executable that runs 'inside' the MS Internet Information Server. But also Word is a COM object:

loWordApp = CREATEOBJECT("Word.Application") --> you can drive and run Word in VFP, even though Word was not written in VFP. But COM is much more than just that. I'll paste a text from The COM Programmer's Cookbook.

Creating a Microsoft® OLE Component Object Model (COM) object simply requires you to expose one or more interfaces that follow the COM rules. There are many other ways to structure software components. What makes COM interesting is that it is a widely accepted interoperability standard. When you use COM to connect pieces of software, deviations from the standard just cause interoperability problems. I mention this because there are many perfectly reasonable variants and alternatives to COM. The problem with these is that they do not interoperate with other COM objects. This cookbook focuses solely on what you can do with COM implementation within the constraints of the COM standard.

A COM class may be registered in the system registry in order to become a COM server. This is an optional step: It increases the usefulness of a COM object but is not required. For COM objects that are part of some larger whole, it is sometimes not appropriate.

The creation of object instances and the use of interfaces obtained from those instances are often done by separate pieces of code. This separation allows the interface user to be attached to different classes at different times, and is an important feature of COM. Most existing software assumes great knowledge about the implementation details of the code that it calls. By deliberately avoiding such coupling, COM encourages a style of programming in which different pieces of code can be truly independent of one another. Rather than assuming knowledge about the implementation of some called code, a COM client assumes a service from an interface or collection of interfaces. Different implementations can provide that service. COM interfaces provide a standard means by which a client of an object can perform an initial negotiation for a particular service and then assume some behavior from that service that conforms to a known contract.

So what is your next step? That is something that you must decide. What is my next step? Mmmmm, maybe i take my two rabbits to Mars.

Eric den Doop
www.foxite.com - The Home Of The Visual FoxPro Experts


how to create my own toolbars or add some of them to my appl Posted by ERNESTO PAEZ @ 5/31/2001 12:00:55 PM
RE: how to create my own toolbars or add some of them to my appl Posted by Eric den Doop @ 5/31/2001 12:49:35 PM
RE: how to create my own toolbars or add some of them to my appl Posted by ERNESTO PAEZ @ 5/31/2001 4:02:56 PM
RE: how to create my own toolbars or add some of them to my appl Posted by Eric den Doop @ 5/31/2001 4:44:04 PM