Datasheet

Figure 1-16

Now before you finish your sample application, let us briefly discuss some coding practices that you

should be using.

Modified Hungarian Notation

You may have noticed that the names given to the controls look a little funny. Each name is prefixed

with a shorthand identifier describing the type of control it is. This makes it much easier to understand

what type of control you are working with when you are looking through the code. For example, say

you had a control called simply Name, without a prefix of

lbl or txt. You would not know whether

you were working with a text box that accepted a name or with a label that displayed a name. Imagine

if, in the previous Try It Out, you had named your label Name1 and your text box Name2 — you would

very quickly become confused. What if you left your application for a month or two and then came back

to it to make some changes?

When working with other developers, it is very important to keep the coding style consistent. One of the

most commonly used styles for control names within application development in many languages was

brought forth by Dr. Charles Simonyi, who worked for the Xerox Palo Alto Research Center (XPARC)

before joining Microsoft. He came up with short prefix mnemonics that allowed programmers to easily

identify the type of information a variable might contain. Since Simonyi is from Hungary, and the pre-

fixes make the names look a little foreign, the name “Hungarian Notation” came into use for this system.

Because the original notation was used in C/C++ development, the notation for Visual Basic 2005 is

termed Modified. The following table shows some of the commonly used prefixes that you shall be

using in this book.

Hungarian Notation can be a real time-saver when you are looking at code someone else wrote or at

code that you wrote months earlier. However, by far the most important thing is to be consistent in your

naming. When you start coding, pick a convention for your naming. It is recommended that you use the

de facto standard Modified-Hungarian for Visual Basic 2005, but it is not required. Once you pick a con-

vention, stick to it. When modifying others’ code, use theirs. A standard naming convention followed

throughout a project will save countless hours when the application is maintained. Now let’s get back to

the application. It’s now time to write some actual code.

Welcome to Visual Basic 2005

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