Book Image

Mastering Windows PowerShell Scripting - Third Edition

By : Chris Dent
Book Image

Mastering Windows PowerShell Scripting - Third Edition

By: Chris Dent

Overview of this book

PowerShell scripts offer a handy way to automate various chores, however working effectively with these scripts can be a difficult task. This comprehensive guide starts with the fundamentals before moving on to advanced-level topics to help you become a PowerShell Core 6.0 expert. The first module, PowerShell Core 6.0 Fundamentals, begins with the new features of PowerShell Core 6.0, installing it on Linux, and working with parameters, objects and .NET classes from within PowerShell Core 6.0. As you make your way through the chapters, you'll see how to efficiently manage large amounts of data and interact with other services using PowerShell Core 6.0. You'll be able to make the most of PowerShell Core 6.0's powerful automation feature, where you will have different methods available to parse data and manipulate regular expressions and Windows Management Instrumentation (WMI). After having explored automation, you will enter the extending PowerShell Core 6.0 module, covering asynchronous processing and desired state configuration. In the last module, you will learn to extend PowerShell Core 6.0 using advanced scripts and filters, and also debug issues along with working on error handling techniques. By the end of this book, you will be an expert in scripting with PowerShell Core 6.0.
Table of Contents (27 chapters)
Free Chapter
1
Section 1: Exploring PowerShell Fundamentals
6
Section 2: Working with Data
16
Section 3: Automating with PowerShell
19
Section 4: Extending PowerShell

Defining an enumeration

An enumeration is a set of named constants. The .NET framework is full of examples of enumerations. For example, the System.Security.AccessControl.FileSystemRights enumeration describes all of the numeric values that are used to define access rights for files or directories.

Enumerations are also used in PowerShell itself, for example, System.Management.Automation.ActionPreference contains the values for the preference variables, such as ErrorActionPreference and DebugPreference.

Enumerations are created using the enum keyword, and this is followed by a list of values:

enum MyEnum {
First = 1
Second = 2
Third = 3
}

Each name must be unique within the enumeration, and must start with a letter or an underscore. The name may contain numbers after the first character. The name cannot be quoted and cannot contain the hyphen character.

The value does...