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Saturday, January 26, 2008 12:47 PM

Form Event Sequences

One of the things that occasionally seems to confuse people is the question of the order in which the events happen when a form is instantiated. The basic answer, in terms of the Form's own events, is given by the acronym "LISA G", which stands for:
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Saturday, August 04, 2007 2:22 PM

Creating Classes with a Factory

This implementation uses the abstract factory pattern to avoid one of the most difficult code maintenance issues. This is the problem that arises whenever we need to change either the class name, or the source library (or both) from which we want to instantiate
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Monday, March 20, 2006 7:47 PM

Writing Better Code (3)

In the third article of this little series I am going to talk about Procedures and Functions. Visual FoxPro, like its ancestors FoxPro and FoxBase supports two different ways of declaring, and calling, code. Creating a Procedure A procedure is simply
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Monday, March 13, 2006 4:43 PM

Writing Better Code (Part 2)

As I noted in the first article in this little series, one of the really great things about Visual FoxPro is that there are usually several different ways of doing the same thing. Unfortunately, this is also one of the worst things about it because, at
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Tuesday, March 07, 2006 3:23 PM

Writing better code (Part 1)

As we all know, Visual FoxPro provides an extremely rich and varied development environment but sometimes too much of a good thing leads us into bad habits.  When writing code there are usually several ways of achieving the same result, but all too
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Sunday, December 04, 2005 7:00 AM

Handling NULL Values in VFP

I was reminded the other day of some of the issues that can arise in code when an unexpected null value is encountered. This led me back to re-visit my understanding of NULL value handling in VFP and that is what this blog is about. Let us begin by considering
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Sunday, September 18, 2005 5:04 PM

Adding Columns in SQL SELECT statements

A common requirement when working with data, irrespective of its source is to be able to add additional columns to the result set ‘on the fly’. This is pretty straightforward if you simply want a new, blank column, just define it directly
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Sunday, September 04, 2005 4:29 PM

Getting a reference to a parent form

It sometimes happens that we have two forms that depend upon one another in some way. Typically one form is called from another requires access to multiple values, or selection criteria, that are defined in its “parent”. I have seen various
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Tuesday, July 19, 2005 5:08 PM

Passing Multiple Values

One of the questions that I see over and over again on the various technical support forums that I frequent is “What is the best way  to pass multiple values from one object to another”. Let’s begin with the simplest case, where
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Friday, May 13, 2005 4:40 PM

Scope in Visual Foxpro - Part 2

As promised, we’ll continue our review of scoping in Visual FoxPro with a look at how scope affects object properties (and methods). I find it makes things easier to think of properties as “variables that are scoped to an object”. In
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Wednesday, May 04, 2005 4:23 AM

Scope in Visual Foxpro - Part 1

Sorry for the delay in posting - things have been a little hectic the past 10 days or so. Anyway, here is the next in my little series of random jottings. This time I'm looking at variable scoping - and next week I'll continue with Properties and Methods.
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Sunday, April 17, 2005 3:45 PM

Customizing Intellisense III

In the final part of this little series we'll look at scripting in Intellisense. The FoxCode Object While the FoxCode table handles the metadata that lies at the heart of the IntelliSense system, the FoxCode Object is what enables us, as developers,
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Sunday, April 10, 2005 2:41 PM

Customizing IntelliSense - II

Last week I began a discussion of the VFP IntelliSense functionality by talking about the configuration of IntelliSense and how to control its various features. The foxcode.dbf table lies at the very heart of the VFP IntelliSense functionality and understanding
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Sunday, April 03, 2005 3:51 PM

Customizing Intellisense - I

One question that seems to come up fairly often is how to control some of the more irritating facets of the Visual FoxPro IntelliSense engine. IntelliSense was first introduced to the developer world in Microsoft Visual Basic 5.0 and has been widely implemented
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Sunday, March 27, 2005 9:27 AM

Designing and Building Classes

Here's another one that I get asked frequently. Just how should you go about designing classes. Of course, there is no single ‘right’ answer, but I have always found it helpful, when considering creating a new class, to ask myself three questions:
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