Eric A. Smith

Active Data Objects

At one time, data access using Microsoft products was one of the worst alphabet soups in the industry. From DAO to RDO to ODBC, you were never sure what the favored data access strategy of the week was. Active Data Objects (ADO), which were introduced in the Chapter 14, is Microsoft’s current attempt at a single, unified data access strategy. Because ADO is used for both client/server and Web programming, you need to learn only a single data-access method. This chapter goes much further with ADO then the brief introduction in the last chapter.

Working with Networks

Most programs written today interact with a network. Whether the network is a company intranet, a Windows NT server-based network, a peer-to-peer network, or the Internet, the inclusion of network access in your programs places an expanded range of control and information at your fingertips—if you know where to look.

Reliable and Flexible Data Validation

“Garbage in, garbage out” is one of the older sayings in the computer industry, and it is absolutely true. If you let garbage data in your system, you have garbage data to work with and no result will be reliable. However, if you don’t allow some flexibility in how the user enters data, users will complain and eventually stop using your system. This chapter shows you how to be both firm and flexible in enforcing data integrity in what users enter in your applications.

Arrays and Array Manipulation

Virtually every type of application, program, and component uses arrays for data storage—regardless of the programming language used. While Visual Basic lets you easily create arrays, it contains no intrinsic methods for most common tasks for working with arrays. You need to write your own subroutines (or take advantage of those written by someone else) for this. For example, commonly, you’ll want to rearrange, or sort, the order of the elements in an array by arranging the elements in ascending order (A–Z, for example) and sometimes in descending order (Z–A).

Windows Help Systems—From the Inside

Usually, you’ll want your Visual Basic applications to be capable of providing users with help. Visual Basic itself offers rudimentary help constructs, but Windows help offers much greater functionality.

WebClasses: A New Way to Program for the Web

Until now, a Web page consisted of a static HTML page or, for Microsoft Internet Information Server (IIS) users, an interpreted Active Server Page (ASP) page. Your Web server wasn’t able to easily run compiled code generated from a familiar product such as Visual Basic—until WebClasses.

Multiple Document Interface Forms

The earliest Visual Basic applications were little more than DOS programs with a friendly, if simple, user interface. You chained each form to the next one, and you probably included a form or two containing a menu of buttons. Now with Windows, however, Visual Basic enables you to create multiwindow applications with richer functionality by providing Multiple Document Interface (MDI) forms.

Localization: The Art of Talking Like a Native

The Internet and the World Wide Web have made for a truly global village. People from literally anywhere in the world can use your software or view your Web pages. Unfortunately, most software displays content in the language of the author, not the user. Using only English puts your software off-limits to most of the world. And if your Web site is for commercial purposes, using an English-only solution effectively limits your potential market. However, Visual Basic and Windows offer powerful localization capabilities that let you write once and run in any language Windows supports—the secrets follow.

Fun with Numbers, Numeric Processing, and Logic

Processing numeric data is fundamental to programming. Although you might not know it, most of the tough questions about numeric processing have already been answered! Ifyou don’t know the answers then perhaps you can figure them out—given enough time. But why waste time? High-bytes, low-words, most significant bits...and more all await you. Read on!

Strings and String Handling

One of the most powerful aspects of Visual Basic—and the envy of developers using most other languages—is the ease with which it lets you work with strings. Visual Basic’s built-in string functions, which were further improved in version 6, are the key to an amazing array of capabilities. Strings are the way that much data is represented, and data handling is what most Visual Basic programs are all about, so this chapter is dedicated to the examination, parsing, and changing of the beloved string.