Vb Com [Paperback]

Thomas Lewis (Author)

Book Description

Publication Date: February 1999

COM has traditionally been considered as something that VB programmers don't need to think about too much: VB is supposed to look after all the nitty gritty of COM, leaving the VB programmers to rapidly develop working business solutions. However, with Microsoft pushing hard on its multi-tiered technologies, more and more people are becoming aware that COM is something important. For any moderately advanced VB programming at all, COM is present - often under the guise of ActiveX. COM underlies most of which is going on in VB. COM is components and objects: and there are hundreds of objects and components even in the basic VB environment. So what's going on? What is COM? Why is it so important? What can VB programmers do with COM? Foe newcomers to COM, this is all a bit mysterious. For competent but relatively non-technical VB professional programmers, the full story of COM is still somewhat disjointed. Meanwhile, a new type of programming consultant is coming into existence: COM design experts. Why? Because as soon as you start writing professional VB applications, you are making COM decisions (or VB is making them for you), whether it is with ActiveX, MTS, DCOM.. and some of these decisions have real implications for the success of your software design and performance.

Editorial Reviews

Amazon.com Review

The Microsoft Component Object Model (COM) is the foundation behind Visual Basic 6, even if Visual Basic (VB) hides most of the inner details. To write better VB programs for the enterprise, chances are you'll need to take on at least some of the intricacies of COM. VB COM: A Visual Basic Programmer's Introduction to COM provides an approachable guide to today's COM and other Microsoft technologies.

The book begins with one of the most approachable and effective tours of COM you're likely to find anywhere. The author covers COM components along with fundamental terms (such as interfaces, globally unique identifiers (GUIDs), IUnknown, and the registry) with a minimum of hassle. In a section on OLE Automation, the author shows how to use VB to script Excel spreadsheets, while explaining the details of early and late binding, IDispatch, and dual interfaces.

Next the author discusses how to build components, starting with ActiveX servers (both dynamic-link libraries [DLLs] and standalone EXEs) and proceeding to ActiveX controls. (The section on building controls is particularly strong, with good coverage of Ambient and Extender objects and connection points for event handling.) Throughout, VB COM relies on tools-based examples, with plenty of screen shots from VB 6 tools (such as its Class Builder Wizard). Later the book moves on to the enterprise with coverage of Distributed COM (DCOM), multitiered architectures, Microsoft Transaction Server (MTS), and emerging standards such as COM+.

In all, VB COM delivers a clear picture of the inner workings of COM for the VB developer with a useful mix of simplicity and essential technical detail. --Richard Dragan

From the Publisher

This book is geared towards the Visual Basic programmer who wants to begin discovering the benefits of Microsoft's Component Object Model (called COM) and how to use COM to build more dynamic applications.

See all Editorial Reviews

Product Details

• Paperback: 345 pages
• Publisher: Peer Information; 1st edition (February 1999)
• Language: English
• ISBN-10: 1861002130
• ISBN-13: 978-1861002136
• Product Dimensions: 9.1 x 7.2 x 1 inches
• Shipping Weight: 1.4 pounds
• Average Customer Review: 4.3 out of 5 stars  See all reviews (42 customer reviews)
• Amazon Best Sellers Rank: #2,345,994 in Books (See Top 100 in Books)

Customer Reviews

Most Helpful Customer Reviews

19 of 19 people found the following review helpful:

4.0 out of 5 stars Readable and thorough COM discussion for VB developers, March 25, 2000

By 

Dr. Robert C.A. Goff, MCSD, MCSE, MCDBA "Coun... (Blacksburg, VA USA) - See all my reviews

This review is from: Vb Com (Paperback)

COM is a programmatic challenge in C++. Unfortunately many in-depth discussions of COM assume that you need to know all those pointer-level details. But as a VB developer, much of COM's interface complexity is handled automatically. Mr. Lewis approaches COM with this understanding.

The text is readable and thorough. Its diagrams have been stripped down to the specifics of each discussion. Even the lollipop diagrams are understandable. (I easily forgive the barnyard analogies.) The author attempts to clarify rather than dazzle. He makes IUnknown feel more like a friend than a stranger.

This is a worthwhile reference on its own, and a good supplemental text when studying for the VB Distributed (i.e., "VB COM") exam, 70-175. Its comfortable writing style belies a richness of content. The author's focus on his target audience is sustained and appropriate. No single book can cover everything (and you really don't want to see everything) about COM.

If you wish to bathe in the ugly realities of COM from a C++ perspective, Prendergast's MCSD Solution Architectures book is painfully detailed, and mostly about COM. (I do not recommend Prendergast for 70-100 exam preparation, if you're a VB developer.)

Weaknesses: Significant performance issues which relate to programming COM, DCOM and MTS are not addressed in great enough depth, nor with great enough emphasis. A good in-process COM object usually makes a dreadful object in MTS. Likewise, the critical need for custom marshaling of parameters to DCOM objects is slighted, as is the disastrous performance penalties of using collections.

A word about errors and editing. In the publishing industry, most book manuscripts require 18 to 36 months to reach the bookshelf. For books on emerging (and rapidly changing) technologies, publishers have gotten the cycle down to an astounding 6 to 9 months. Hence, more errors. My experience with Wrox books is that the errors are few, and tend to be typographical. Their technical editors are among the most thorough in the industry. In this particular book, the occasional errors are inconsequential.

Conclusion: If you are a VB developer who needs to learn more about COM, this is a solid choice. If you are a 70-175 exam candidate, read this book and enjoy that warm deja vu satisfaction after passing the exam. If you'll be doing COM with C++, buy a different book.

17 of 18 people found the following review helpful:

5.0 out of 5 stars A excellent introduction to how COM & VB work together., March 1, 1999

By A Customer

This review is from: Vb Com (Paperback)

VBCOM by Thomas Lewis provides an excellent insight to the how VB programmers can use the power of Microsoft's Component Object Model (COM) to develop robust components for todays distributed applications.

This book is really aimed at beginners/inexperienced programmers who are just starting out with VB, but is also very useful to experianced programmers like me who just want to know more about COM, as it provides information and documentation that just can not be found in the VB on-line help.

The book gives the reader an excellent introduction to COM, and then goes on to discuss DCOM, ActiveX control and MTS development, giving tips on how these technologoies are best used. The book also has a good chapter on the future of COM, otherwise known as COM+ & DNA (Distributed interNet Architecture), so you also get an insight into Windows 2000, and Microsofts visions for the future of distributed component development.

By the end of the book you will appreciate how important a good understanding of COM is for really successful VB development, and how COM is actually very simple yet so powerful once you understand the basic concepts such as components, interfaces & coclasses.

Looking forward to the next book in the series.

Rich. VB/C++ Programmer.

15 of 16 people found the following review helpful:

5.0 out of 5 stars Gets the VB developer up to speed in COM in a week !!!, May 20, 1999

By A Customer

This review is from: Vb Com (Paperback)

I stay away from books with the pharse "learn XXXX in XX days" in the title as if they are the plague. And I have always been a little leary of books with the word "Introduction" in the title.

I read this book on the recommendation of a friend, and former collegue, to determine if it was an appropriate publication to get about 6 of our begining VB programers, ex fox pro guys, up to speed on COM.

This book not only met my criteria for this application but I found myself continually shaking my head in agreement with the author while I read the book. His methodologies are VERY sound and his approach to teaching COM is EXTREMELY easy to follow. Also, the author's writing style is very easy to read. This is NOT a 2 asprin per chapter book and I read it in about 4 days.

This book is a PRICELESS tool to get begining and seasoned VB programmers up to speed in COM. I promise you that you will be able to converse intelligently about COM in a week.

Mr.Lewis... I owe you a cold one!

Steve

PS. My only minor qualm with the book would be the step by step screen shots. However, for the intended audience of this book, I can see how they would be helpful.