Re: VFP Objects for a beginner - help!

These are deceptively HUGE and complex questions. LOL

An "object" (which really only exists at runtime) is nothing but a blob that
contains some data and some code. It may or may not do something useful.

Using your "Hello World" as an example, you'd start with a class definition
that might look like this:

Define Class myTextFileMaker As Session
textmessage = ""
Procedure SetMessage(somestring)
this.textmessage = somestring
Endproc
Procedure WriteFile(filename)
StrToFile(this.textmessage,filename)
Endproc
Enddefine

You'd call that this way:

ox = CreateObject("MyTextFileMaker")
ox.SetMessage("Hello World")
ox.WriteFile("c:\hello.txt")
ox.Release()

IOW, OOP is nothing but new packaging on well-organized code. There are
general concepts, though. You'll notice "As Session" in the class definition
above. That means that myTextFileMaker will *inherit* all of the properties
and behaviors of VFP's Session class, including the Release() method that I
called.

To go much deeper into this would be unproductive in a newsgroup post, but
fortunately there are LOTS of books available to you. Go to
www.hentzenwerke.com and have a look around. "Fundamentals" would probably
be good since it presumes fore-knowledge of previous versions of Fox. If you
can find a copy, look for Savannah Brentnall's "Object Oriented Programming
in Visual Foxpro" (not a Hentzenwerke title, unfortunately).

And come back here when you have specific questions!

Dan




JWB wrote:
I'm an self-taught old-school programmer who uses VFP 6 and,
embarassingly, never got in to exploiting the power of objects.
Although very fast and optimized, all my code constists of function
calls, passing and returning paramters, etc. I want to begin porting
some of these paramterized functions in to objects that I can use
from within this app but also distribute so that another guy who is a
VB .net programmer can drop in his app. Hope I'm stating this
correctly so far.

So my question is, how do I get started? I read the help stuff and
it's foreign to me as I try and relate it to a paramterized function.
If I wanted to create an object in VFP that did some lowly task just
for the sake of doing it, for example...writing a text file that
contains the text "Hello World", how would Io that?

- Ben


.

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