Windows PowerShell Cookbook ™ Other Microsoft .NET resources from O’Reilly Related titles Windows PowerShell Quick Windows Vista Reference Administration Windows Server 2008: The Windows Vista: The Definitive Guide Definitive Guide .NET Books dotnet.oreilly.com is a complete catalog of O’Reilly’s books on Resource Center .NET and related technologies, including sample chapters and code examples. ONDotnet.com provides independent coverage of fundamental, interoperable, and emerging Microsoft .NET programming and web services technologies. Conferences O’Reilly brings diverse innovators together to nurture the ideas that spark revolutionary industries. We specialize in document- ing the latest tools and systems, translating the innovator’s knowledge into useful skills for those in the trenches. Visit con- ferences.oreilly.com for our upcoming events. Safari Bookshelf (safari.oreilly.com) is the premier online refer- ence library for programmers and IT professionals. Conduct searches across more than 1,000 books. Subscribers can zero in on answers to time-critical questions in a matter of seconds. Read the books on your Bookshelf from cover to cover or sim- ply flip to the page you need. Try it today for free. Windows PowerShell Cookbook™ Lee Holmes Beijing • Cambridge • Farnham • Köln • Paris • Sebastopol • Taipei • Tokyo Windows PowerShell Cookbook™ by Lee Holmes Copyright © 2008 Lee Holmes. All rights reserved. Printed in the United States of America. Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472. O’Reilly books may be purchased for educational, business, or sales promotional use. Online editions are also available for most titles (safari.oreilly.com). For more information, contact our corporate/institutional sales department: (800) 998-9938 or [email protected]. Editor: John Osborn Cover Designer: Karen Montgomery Production Editor: Laurel R.T. 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ISBN-10: 0-59652-849-3 ISBN-13: 978-0-596-652849-2 [M] Table of Contents Foreword . xvii Preface . xxi Part I. Tour A Guided Tour of Windows PowerShell . 3 Introduction 3 An Interactive Shell 4 Structured Commands (Cmdlets) 6 Deep Integration of Objects 7 Administrators As First-Class Users 8 Composable Commands 9 Techniques to Protect You from Yourself 9 Common Discovery Commands 10 Ubiquitous Scripting 11 Ad Hoc Development 12 Bridging Technologies 12 Namespace Navigation Through Providers 14 Much, Much More 16 Part II. Fundamentals 1. The Windows PowerShell Interactive Shell . 19 1.0 Introduction 19 1.1 Run Programs, Scripts, and Existing Tools 19 1.2 Run a PowerShell Command 21 v 1.3 Customize Your Shell, Profile, and Prompt 22 1.4 Find a Command to Accomplish a Task 25 1.5 Get Help on a Command 26 1.6 Program: Search Help for Text 28 1.7 Invoke a PowerShell Script From Outside PowerShell 29 1.8 Program: Retain Changes to Environment Variables Set by a Batch File30 1.9 Get the System Date and Time 32 1.10 Determine the Status of the Last Command 33 1.11 Measure the Duration of a Command 34 1.12 Customize the Shell to Improve Your Productivity 35 1.13 Program: Learn Aliases for Common Commands 36 1.14 Access and Manage Your Console History 38 1.15 Store the Output of a Command into a File 39 1.16 Add Information to the End of a File 41 1.17 Record a Transcript of Your Shell Session 41 1.18 Display the Properties of an Item As a List 42 1.19 Display the Properties of an Item As a Table 42 1.20 Manage the Error Output of Commands 44 1.21 Configure Debug, Verbose, and Progress Output 45 1.22 Extend Your Shell with Additional Snapins 47 1.23 Use Console Files to Load and Save Sets of Snapins 48 2. Pipelines . 49 2.0 Introduction 49 2.1 Filter Items in a List or Command Output 50 2.2 Program: Simplify Most Where-Object Filters 51 2.3 Program: Interactively Filter Lists of Objects 52 2.4 Work with Each Item in a List or Command Output 54 2.5 Automate Data-Intensive Tasks 56 3. Variables and Objects . 61 3.0 Introduction 61 3.1 Store Information in Variables 62 3.2 Access Environment Variables 63 3.3 Control Access and Scope of Variables and Other Items 65 3.4 Work with .NET Objects 67 3.5 Create an Instance of a .NET Object 71 3.6 Program: Create Instances of Generic Objects 73 3.7 Reduce Typing for Long Class Names 74 vi | Table of Contents 3.8 Use a COM Object 76 3.9 Learn About Types and Objects 77 3.10 Get Detailed Documentation About Types and Objects 78 3.11 Add Custom Methods and Properties to Objects 80 3.12 Add Custom Methods and Properties to Types 82 4. Looping and Flow Control . 87 4.0 Introduction 87 4.1 Make Decisions with Comparison and Logical Operators 87 4.2 Adjust Script Flow Using Conditional Statements 89 4.3 Manage Large Conditional Statements with Switches 90 4.4 Repeat Operations with Loops 91 4.5 Add a Pause or Delay 93 5. Strings and Unstructured Text . 95 5.0 Introduction 95 5.1 Create a String 95 5.2 Create a Multiline or Formatted String 97 5.3 Place Special Characters in a String 98 5.4 Insert Dynamic Information in a String 99 5.5 Prevent a String from Including Dynamic Information 100 5.6 Place Formatted Information in a String 101 5.7 Search a String for Text or a Pattern 102 5.8 Replace Text in a String 105 5.9 Convert a String to Upper/Lowercase 106 5.10 Trim a String 107 5.11 Format a Date for Output 108 5.12 Program: Convert Text Streams to Objects 110 5.13 Generate Large Reports and Text Streams 114 6. Calculations and Math . 117 6.0 Introduction 117 6.1 Perform Simple Arithmetic 117 6.2 Perform Complex Arithmetic 119 6.3 Measure Statistical Properties of a List 121 6.4 Work with Numbers As Binary 123 6.5 Simplify Math with Administrative Constants 127 6.6 Convert Numbers Between Bases 128 Table of Contents | vii Part III. Common Tasks 7. Simple Files . 133 7.0 Introduction 133 7.1 Get the Content of a File 133 7.2 Search a File for Text or a Pattern 135 7.3 Parse and Manage Text-Based Logfiles 136 7.4 Parse and Manage Binary Files 139 7.5 Create a Temporary File 141 7.6 Search and Replace Text in a File 143 8. Structured Files . 147 8.0 Introduction 147 8.1 Access Information in an XML File 147 8.2 Perform an XPath Query Against an XML File 150 8.3 Modify Data in an XML File 151 8.4 Easily Import and Export Your Structured Data 153 8.5 Store the Output of a Command in a CSV File 155 8.6 Import Structured Data from a CSV File 156 8.7 Use Excel to Manage Command Output 157 9. Internet-Enabled Scripts . 160 9.0 Introduction 160 9.1 Download a File from the Internet 160 9.2 Download a Web Page from the Internet 161 9.3 Program: Get-PageUrls 163 9.4 Program: Connect-WebService 166 9.5 Export Command Output As a Web Page 170 9.6 Program: Send an Email 170 9.7 Program: Interact with Internet Protocols 172 10. Code Reuse . 176 10.0 Introduction 176 10.1 Write a Script 176 10.2 Write a Function 179 10.3 Write a Script Block 180 10.4 Return Data from a Script, Function, or Script Block 182 10.5 Place Common Functions in a Library 184 10.6 Access Arguments of a Script, Function, or Script Block 185 viii | Table of Contents 10.7 Access Pipeline Input 188 10.8 Write Pipeline-Oriented Scripts with Cmdlet Keywords 189 10.9 Write a Pipeline-Oriented Function 193 11. Lists, Arrays, and Hashtables . 195 11.0 Introduction 195 11.1 Create an Array or List of Items 195 11.2 Create a Jagged or Multidimensional Array 197 11.3 Access Elements of an Array 198 11.4 Visit Each Element of an Array 199 11.5 Sort an Array or List of Items 200 11.6 Determine Whether an Array Contains an Item 200 11.7 Combine Two Arrays 201 11.8 Find Items in an Array That Match a Value 202 11.9 Remove Elements from an Array 203 11.10 Find Items in an Array Greater or Less Than a Value 204 11.11 Use the ArrayList Class for Advanced Array Tasks 205 11.12 Create a Hashtable or Associative Array 206 11.13 Sort a Hashtable by Key or Value 207 12.