To convert MBR to GPT from PowerShell without losing data, run Windows’ built-in MBR2GPT tool from an elevated window, validate first, then convert, and switch the firmware to UEFI: MBR2GPT only handles the system disk, the one Windows boots from. Below I check the partition style, test a disk against MBR2GPT’s rules, cover BitLocker and … Read more
To write an XML object to a file in PowerShell, call the Save() method of the [xml] document with a full path. It writes indented XML that other programs can read: Two details trip people up: relative paths in Save(), and piping XML to Out-File. Below I cover both, plus building XML from scratch, controlling … Read more
To convert HTML to JSON in PowerShell, pull the data out of the HTML into objects first, then pipe the objects to ConvertTo-Json. For a clean table, the quickest way is to cast the HTML to [xml]: Real web pages are rarely clean enough for that. Below I cover the [xml] route, why it breaks … Read more
Most PowerShell interview questions come back to one idea: PowerShell passes .NET objects, not text. If you can show that in two lines, you’ve answered half the screening round already: Output: Get-Item returned a FileInfo object, so the file size is a real number you can sort, compare and add up. A text-based shell would … Read more
Need a random number between 1 and 10? To generate random numbers in PowerShell, call Get-Random with a range, and remember the maximum is never returned: That prints a whole number from 1 to 10. Below, I cover decimals, several numbers at once, seeds, 6-digit codes, .NET options and secure numbers, each tested in PowerShell … Read more
PowerShell pipeline variables come in two kinds: the automatic $_ (also called $PSItem), which holds the current object, and the -PipelineVariable common parameter, which saves an object under your own name for later pipeline steps: Output: Here $order still points at the CSV row two commands later, while $PSItem is whatever reached the current command. … Read more
The fastest way to get the computer name in PowerShell is the COMPUTERNAME environment variable. Type this and press Enter: It works the same in PowerShell 7 and Windows PowerShell 5.1 on Windows. The other methods below return almost the same thing, but they differ in letter case, in remote support, and on Linux or … Read more
To convert a relative path to an absolute path in PowerShell, use Resolve-Path. It resolves the path against your current PowerShell location and returns the full path: Resolve-Path only works for paths that exist, though, and the popular .NET shortcut can quietly use the wrong folder. Below I cover both problems, plus paths relative to … Read more
To count occurrences of a substring in a string in PowerShell, escape the substring and count the regex matches. This one line returns how many times $find appears in $text: The count you get depends on case, special characters and overlaps, and a few popular shortcuts quietly get it wrong. I ran each method below … Read more
To convert an object to a string in PowerShell, pipe it to Out-String, which returns the same text you’d see in the console. Add .Trim() to drop the blank lines around it: That works for custom objects, cmdlet output and hashtables. When you want one value in a sentence, you’ll use property expansion, JSON or … Read more