Powershell

A collection of some powershell-snippets I found useful, can be found under:

• https://github.com/hmaier-dev/powershell-library/tree/main/src

History#

You can get the history of your current powershell session with Get-History. To access older history, you can use the file stored under (Get-PSReadLineOption).HistorySavePath. In this file a maximum of (Get-PSReadLineOption).MaximumHistoryCount commands is stored.

With fzf you can access this list comfortably:

function FuncFuzzySearchHistory(){
  $cmd =  $(Get-Content $((Get-PSReadLineOption).HistorySavePath) | fzf)
  $cmd
  Invoke-Expression $cmd
}

Prompt#

To change the behaviour of the powershell prompt before running the command, alter the prompt-function.

## This sets the window-title with the last three dir of the path
function prompt(){
  $three = (Get-Location).Path -split '\\' | Select-Object -Last 3
  $path = $three[0] + "\" + $three[1] + "\" + $three[2] 
  $host.ui.RawUI.WindowTitle = $path
  "$(Get-Location)> "
}

Constructing an alias with arguments#

You can use the builtin-args variable for that.

function DotFilesRepo(){
	$base = "git.exe --git-dir=$env:USERPROFILE\repos\dotfiles\ --work-tree=$env:USERPROFILE"
	$cmd = "$base $args" # The $args-variable is builtin and gets all arguments. Discoverd by accident.
	Invoke-Expression -Command $cmd
}

function DotFilesReposStatus(){
    dfr status
}

Set-Alias -Name dfr -Value DotFilesRepo
Set-Alias -Name dfrs -Value DotFilesReposStatus

Aliases#

When constructing an alias with the corresponding function, keep in mind that powershell is not case-sensitive. That means, Set-Alias -Name wiki -Value Wiki would set alias that overwrites the function. My approach to this is to add the appropriate verb to the function name, e.g. Set-Alias -Name wiki -Value EnterWiki.

Params#

If you want to use flags to activate a function, you can use a [switch].

param(
    [switch]$SetTaskScheduler = $False,
)

Write-Host $SetTaskScheduler
if ($SetTaskScheduler){
    Write-Host "Setting the task"
}

Task Scheduler#

• nice article: https://www.sharepointdiary.com/2022/06/create-scheduled-task-in-powershell.html

Credentials Object#

If you want to safely pass username and password, you can create a Credentials object

$username = "admin1234"
$password = "mysupersecurepassword"

[securestring]$secStringPassword = ConvertTo-SecureString $password -AsPlainText -Force
[pscredential]$cred = New-Object System.Management.Automation.PSCredential ($username, $secStringPassword)

Powershell Data File#

Instead of using json, yaml or another well-known config-file format for your script, you can go the native powershell way with psd1-file.

A simple one-dimensional config (e.g. config.psd1) would look like this:

@{
    Username = "ftp-user"
    Password = "supersecretftppassword"
    Exclude = @("PT*0730*.DAT")
}

In your script you would import the config-file and access the variable like properties:

$config = Import-PowershellDataFile -Path ".\config.psd1"
$config.Username
$config.Password
$config.Exclude

Tips and Tricks#

Get all line of go#

Get-ChildItem -Recurse -Include '*.go' | Get-Content | Measure-Object -Line