Table Of Content00 973x FM 8/28/00 2:22 PM Page i
Scot Hillier’s COM+ Programming
with Visual Basic®
Scot Hillier
800 East 96th St.,Indianapolis,Indiana,46240 USA
00 973x FM 8/28/00 2:22 PM Page ii
Copyright ©2000 by Sams Publishing ASSOCIATEPUBLISHER
Bradley L. Jones
FIRSTEDITION
All rights reserved. No part of this book shall be reproduced,stored in a ACQUISITIONSEDITOR
retrieval system,or transmitted by any means,electronic,mechanical,photo- Sharon Cox
copying,recording,or otherwise,without written permission from the pub-
DEVELOPMENTEDITOR
lisher. No patent liability is assumed with respect to the use of the information
Susan Shaw Dunn
contained herein. Although every precaution has been taken in the preparation
of this book,the publisher and author assume no responsibility for errors or MANAGINGEDITOR
omissions. Neither is any liability assumed for damages resulting from the use Charlotte Clapp
of the information contained herein. For information,address Sams Publishing,
PROJECTEDITOR
A division of Macmillan Computer Publishing,201 W. 103rd St.,Indianapolis,
Paul Schneider
IN 46290.
International Standard Book Number:0-672-31973-X COPYEDITOR
Rhonda Tinch-Mize
Library of Congress Catalog Card Number:00-102598
INDEXER
Printed in the United States of America
Chris Barrick
First Printing:September 2000
PROOFREADER
03 02 01 00 4 3 2 1
Kimberly Campanello
Interpretation of the printing code:the rightmost double-digit number is the
TECHNICALEDITOR
year of the book’s printing; the rightmost single-digit,the number of the
Rick Anderson
book’s printing. For example,a printing code of 98-1 shows that the first print-
ing of the book occurred in 1998. TEAMCOORDINATOR
Meggo Barthlow
Composed in Function Condensed,AGaramond and MCPdigital by Macmillan
Computer Publishing SOFTWARESPECIALISTS
William Eland,Jr.
Trademarks
Dan Scherf
All terms mentioned in this book that are known to be trademarks or service
marks have been appropriately capitalized. Sams Publishing cannot attest to INTERIORDESIGNER
the accuracy of this information. Use of a term in this book should not be Anne Jones
regarded as affecting the validity of any trademark or service mark. COVERDESIGNER
Aren Howell
Warning and Disclaimer
Every effort has been made to make this book as complete and as accurate as LAYOUTTECHNICIANS
possible,but no warranty or fitness is implied. The information provided is on Ayanna Lacey
an “as is”basis. The author and the publisher shall have neither liability nor Heather Hiatt Miller
responsibility to any person or entity with respect to any loss or damages aris- Stacey Richwine-DeRome
ing from the information contained in this book or from the use of the CD or
programs accompanying it.
00 973x FM 8/28/00 2:22 PM Page iv
Contents
INTRODUCTION 1
How This Book Is Organized..................................................................1
Part I:Understanding COM+ Applications........................................1
Part II:Data Services..........................................................................2
Part III:Business Services..................................................................3
Part IV:User Services........................................................................3
Part V:PubsOnLine.com....................................................................4
Conventions Used in This Book..............................................................5
PART I UNDERSTANDINGCOM+ APPLICATIONS 7
1 WINDOWSDNAANDCOM+ 9
Windows 2000 Services........................................................................11
Active Directory ..............................................................................12
Internet Information Server 5.0........................................................12
Message Queuing ............................................................................14
Universal Data Access......................................................................14
XML Support....................................................................................14
Network Load Balancing..................................................................16
Component Services ........................................................................16
Tiered Architecture Overview................................................................18
Two-Tier Architecture......................................................................19
Three-Tier Architecture....................................................................21
Establishing a Test Environment ..........................................................23
Windows 2000 Advanced Server......................................................24
SQL Server 2000..............................................................................26
Visual Studio....................................................................................26
2 ADMINISTERINGCOM+ 27
The Component Services Explorer........................................................28
Computer Properties ........................................................................29
Application Properties......................................................................34
The System Application ..................................................................40
Creating Applications ......................................................................40
Component Properties......................................................................42
Installing COM+ Components into an Application ........................46
3 DESIGNINGCOM+ APPLICATIONS 53
Assessing Functional Requirements......................................................54
Problem Statement............................................................................54
Gathering Requirements ..................................................................55
Assessing Requirements ..................................................................57
00 973x FM 8/28/00 2:22 PM Page v
Describing the System ..........................................................................58
Identifying Actors and Use Cases....................................................59
Documenting the Use Cases............................................................60
Flow Charts......................................................................................64
Creating the Paper Prototype ................................................................65
System Modeling..............................................................................66
Database Model................................................................................66
Logical Model..................................................................................67
Three-Tier Diagram..........................................................................69
4 COM+ APPLICATIONFUNDAMENTALS 83
Understanding Contexts........................................................................84
Object Activation ..................................................................................88
Communicating with the Context....................................................93
State Management............................................................................96
The ObjectControl Interface............................................................99
Managing Shared Properties................................................................102
SharedPropertyGroupManager................................................102
SharedPropertyGroup................................................................102
SharedProperty..........................................................................103
PART II DATASERVICES 111
5 ACCESSINGDATAWITHCOM+ 113
OLEDB Session Pooling ....................................................................114
Controlling the Number of Pools ..................................................115
Tuning Session Pooling..................................................................117
Understanding Data Transportation ....................................................123
Understanding Cursors ..................................................................123
Understanding Transports and Payloads........................................125
Delimited Strings............................................................................126
Variant Arrays ................................................................................127
Disconnected Recordsets................................................................129
Property Bags ................................................................................131
Conclusion......................................................................................134
XML....................................................................................................134
XML Fundamentals........................................................................135
The Stream Object..........................................................................139
Web Services and SOAP................................................................141
Updating Records................................................................................142
Handling Collisions........................................................................143
00 973x FM 8/28/00 2:22 PM Page vi
vi
SCOTHILLIER’SCOM+ PROGRAMMINGWITHVISUALBASIC
6 COM+ DATACOMPONENTS 149
Encapsulating Stored Procedures........................................................151
Parameter Passing................................................................................154
Strong Function Signatures............................................................154
Variant Arrays ................................................................................155
XML ..............................................................................................158
Error Handling ....................................................................................161
Polymorphic Interfaces........................................................................163
Understanding Polymorphism........................................................164
Creating Standards..........................................................................165
The DNA Payload................................................................................167
Overview........................................................................................169
Dataset Properties and Methods ....................................................169
Field Object Properties ..................................................................170
Passing Parameters with the DNA Payload ..................................170
Returning Data with the DNA Payload..........................................173
Displaying HTML with the DNA Payload....................................174
Conclusion ..........................................................................................175
7 COM+ TRANSACTIONS 181
Understanding Transaction Attributes ................................................182
The Microsoft Distributed Transaction Coordinator ..........................183
Transactional Components..................................................................184
Understanding Transaction Context ..............................................185
Voting in Transactions....................................................................190
Monitoring Transactions......................................................................198
PART III BUSINESSSERVICES 205
8 COM+ SECURITY 207
Distributed Security ............................................................................208
Certificates......................................................................................208
Kerberos Protocol ..........................................................................209
Active Directory..................................................................................210
Single Sign-On ..............................................................................211
Microsoft Installer..........................................................................211
Personalization................................................................................212
Active Directory Services Interface....................................................213
Using ADSI....................................................................................213
Manipulating Properties ................................................................216
Authenticating Users......................................................................220
COM+ Security Features ....................................................................222
Declarative Security ......................................................................222
Programmatic Security ..................................................................223
Conclusion ..........................................................................................226
00 973x FM 8/28/00 2:22 PM Page vii
vii
CONTENTS
9 COM+ BUSINESSFEATURES 231
The COM+ Event System....................................................................232
Event Classes..................................................................................233
Event Subscribers ..........................................................................234
Event Publishers ............................................................................237
Filtering Events..............................................................................238
COM+ Constructors............................................................................238
Compensating Resource Manager System..........................................242
CRM Workers ................................................................................242
CRM Clerks....................................................................................243
Compensating Resource Managers................................................245
CRM Issues....................................................................................249
10 ASYNCHRONOUSCOM+ APPLICATIONS 255
The Microsoft Message Queue............................................................256
MSMQ Applications............................................................................258
MSMQApplication Object ............................................................258
MSMQQuery Object......................................................................259
MSMQQueueInfos Object..............................................................260
MSMQQueueInfo Object ..............................................................260
MSMQQueue Object......................................................................261
MSMQEvent Object ......................................................................261
MSMQMessage Object..................................................................262
MSMQ Limitations........................................................................264
Queued Components............................................................................265
Designing Queued Components ....................................................266
Calling Queued Components..........................................................268
Using Queued Components in Transactions..................................271
Exception Classes ..........................................................................272
PART IV USERSERVICES 279
11 COM+ ANDTHEINTERNET 281
New Internet Information Server Features..........................................282
Isolating Internet Applications ......................................................282
Generating Custom Error Messages..............................................285
Using Scriptless ASP......................................................................290
Creating Transactional Web Pages......................................................290
Understanding Transactional Attributes ........................................290
Creating Multi-Page Transactions..................................................292
Creating Classes in Scripts ............................................................294
00 973x FM 8/28/00 2:22 PM Page viii
viii
SCOTHILLIER’SCOM+ PROGRAMMINGWITHVISUALBASIC
Accessing ASP Objects with COM+ Components..............................298
Understanding XSL Style Sheets........................................................300
XSL Fundamentals ........................................................................300
XSL Templates ..............................................................................302
XSL Elements................................................................................305
12 COM+ ANDWIN32 311
Maintaining Application State ............................................................312
Custom Collections........................................................................314
Data Binding..................................................................................315
User Interface Strategies......................................................................319
ActiveX Controls............................................................................319
HTA Pages......................................................................................324
13 INTEGRATINGCOM+WITHGROUPWARE 331
Integrating Exchange 2000 Server with COM+..................................332
Understanding Web Storage ..........................................................332
ActiveX Data Objects:Accessing Web Stores ..............................334
Collaboration Data:Using Contact and Message Objects ............336
Integrating Microsoft Outlook 2000 with COM+ ..............................338
The Outlook Design Environment ................................................340
Coding Outlook Items....................................................................343
Integrating Digital Dashboards with COM+ ......................................348
14 DEBUGGINGANDDEPLOYINGCOM+ APPLICATIONS 353
Debugging COM+ Components..........................................................354
Debugging in Visual Basic ............................................................354
Debugging in Visual InterDev........................................................355
Deploying COM+ Applications ..........................................................356
Deploying Data Services................................................................357
Deploying Business Services ........................................................357
Deploying User Services................................................................359
Deployment Checklist....................................................................362
Analyzing COM+ Applications ..........................................................363
The Testing Process........................................................................364
Assessing Performance..................................................................366
Load Balancing..............................................................................367
15 COM+ CATALOGADMINISTRATION 377
The COM+ Administration Object Model..........................................378
TheCOMAdminCatalogObject ....................................................378
TheCOMAdminCatalogCollectionObject................................380
TheCOMAdminCatalogObjectObject........................................382
00 973x FM 8/28/00 2:22 PM Page ix
ix
CONTENTS
Performing COM+ Administration with the Windows
Scripting Host....................................................................................383
The WScript Object........................................................................384
The Shell Object ............................................................................385
PART V PUBSONLINE.COM 389
16 DESIGNINGTHEPUBSONLINE.COMAPPLICATION 391
Problem Statement ..............................................................................392
Gathering Requirements......................................................................392
Membership and Personalization ..................................................393
Promotions......................................................................................393
Analysis..........................................................................................393
Identifying Actors and Use Cases........................................................393
Log In ............................................................................................394
Add Book to Cart ..........................................................................397
View Cart........................................................................................399
Checkout ........................................................................................401
Screen Shots and the Paper Prototype ................................................403
Data Model..........................................................................................407
System Models....................................................................................408
The Three-Tier Model....................................................................408
Log In ............................................................................................410
Add Book to Cart ..........................................................................412
Check Out ......................................................................................414
Defining Components..........................................................................415
17 BUILDINGTHEPUBSONLINE.COMAPPLICATION 417
Development Environment..................................................................418
Creating the Database..........................................................................419
Creating the COM+ Components........................................................425
Data Services..................................................................................428
Business Services ..........................................................................436
Deploying Components..................................................................440
Creating the Web Interface..................................................................445
Index 449
02 973x Part I 8/28/00 2:18 PM Page 7
PART
Understanding COM+ I
Applications
IN THIS PART
1 Windows DNA and COM+ 9
2 Administering COM+ 27
3 Designing COM+ Applications 53
4 COM+ Application Fundamentals 83
03 973x CH01 8/28/00 2:22 PM Page 9
Windows DNA and COM+ CHAPTER
1
IN THIS CHAPTER
• Windows 2000 Services 11
• Tiered Architecture Overview 18
• Establishing a Test Environment 23
