Book Image

Mastering Windows PowerShell Scripting (Second Edition) - Second Edition

By : Brenton J.W. Blawat
Book Image

Mastering Windows PowerShell Scripting (Second Edition) - Second Edition

By: Brenton J.W. Blawat

Overview of this book

PowerShell scripts offer a handy way to automate various chores. Working with these scripts effectively can be a difficult task. This comprehensive guide starts from scratch and covers advanced-level topics to make you a PowerShell expert. The first module, PowerShell Fundamentals, begins with new features, installing PowerShell on Linux, working with parameters and objects, and also how you can work with .NET classes from within PowerShell. In the next module, you’ll see how to efficiently manage large amounts of data and interact with other services using PowerShell. You’ll be able to make the most of PowerShell’s powerful automation feature, where you will have different methods to parse and manipulate data, regular expressions, and WMI. After automation, you will enter the Extending PowerShell module, which covers topics such as asynchronous processing and, creating modules. The final step is to secure your PowerShell, so you will land in the last module, Securing and Debugging PowerShell, which covers PowerShell execution policies, error handling techniques, and testing. By the end of the book, you will be an expert in using the PowerShell language.
Table of Contents (24 chapters)
Title Page
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Comparison operators


PowerShell has a wide variety of comparison operators:

  • Equal to and not equal to: -eq and -ne
  • Like and not like: -like and -notlike
  • Greater than and greater than or equal to: -gt and -ge
  • Less than and less than or equal to: -lt and -le
  • Contains and not contains: -contains and -notcontains
  • In and not in: -in and -notin

Case-sensitivity

None of the comparison operators are case sensitive by default. Each of the comparison operators has two additional variants, one which explicitly states it is case-sensitive, and another which explicitly states it is case-insensitive.

For example, the following statement returns true:

'Trees' -eq 'trees' 

Adding a c modifier in front of the operator name forces PowerShell to make a case-sensitive comparison. The following statement will return false:

'Trees' -ceq 'trees' 

In addition to this the case-sensitive modifier, PowerShell also has an explicit case-insensitive modifier:

'Trees' -ieq 'trees' 

However, as case insensitive comparison is the default...