One of the most powerful features of PowerShell is its ability to retrieve and manipulate data. Many a times when you retrieve data from a PowerShell session, the format in which it is available is different from what you would want to display in the PowerShell window or in a log file. For this purpose, PowerShell provides powerful cmdlets and methods to perform data manipulation to best suit your needs as a PowerShell scripter.

While reading this chapter, you'll learn the following concepts:

PowerShell is a powerfulmathematics calculator. In fact, PowerShell has an entire Windows class dedicated to mathematics calculations that can be called by using the[System.Math] .NET class. When you are working with the[System.Math] classes, it is common to callstatic fields within a class. Static fields are static properties, methods, and objects that can be called to display data or do actions. To call a static field, you call the[Math](shortened version of[System.Math]) class, followed by two colons:: and the static field name.

To use the math operation to calculate pi, execute the following command:

[math]::pi

The output of this is shown in the following screenshot:

This simple command will providePI if you ever need it for a calculation by using thepimethod of the math class. The result of this command returns3.14159265358979.

To use the math operation to calculate Euler's number, execute the following command:

[math]::e

The output of this...

When you arescripting, there are times where you may need to get the date andtime of a system. PowerShell offers theget-date cmdlet, which provides the date and time in many different formats of your choice.

To obtain the date object, execute the following command:

$time = get-date$time

The output of this is shown in the following screenshot:

The standardget-date cmdlet, without any triggers, will generate the long date and time format. When you store thedate object in a variable, it is important to remember that the data captured from the cmdlet is a snapshot in time. You'll have to call theget-date cmdlet again to get new values for the updated date and time.

The following table displays all of the date time formatting codes:

While developing scripts, youmay run into instances where you may want to force a specific data type. This is helpful in cases where PowerShell automatically interprets the output from a command incorrectly. You can force data types by the use of brackets specifying a data type and a variable.

To force a string data type, execute the following command:

[string]$myString = "Forcing a String Container"$myString

The output of this is shown in the following screenshot:

The preceding command forces the string data type to the$myString variable. The result is that the$myString variable will always remain a string. It is important to know that if the object or item that you are trying to force to a data type doesn't have a direct conversion to that data type, it will throw an error or exception. This would be the case if you try to insert a string into an integer data type.

To force a string data type and generate a data exception, execute the following command...

The concept of piping isn't anything new to the scripting world. Piping, by definition, is directing the output of an object to another object. When you use piping in PowerShell, you are taking the output of one command and sending the data for use with another section of code. The manipulation can be either to a more legible format, or can be byselecting a specific object and digging deeper into those attributes. A pipe is designated by the '|' symbol and is used after you enter a command. The construct of a pipe looks like this:command | ResultManipulation | SortingObjects. If you need to access the individual items in the pipeline, you can leverage the pipeline output$_ command. This tells the pipeline to evaluate the results from the pipeline and their attributes.

The pipeline offers a wide variety of uses; you can leverage commands such assort-object to sort by a specific attribute,format-list to format the objects into a list, and even theselect...

$a = "Error: This is an example error"$a.toUpper()

$string = "The MAC Address is "$mac = "00:A0:AA:BB:CC:DD"$message = $string + $mac.toLower()$message