{"id":76011,"date":"2016-01-02T00:01:00","date_gmt":"2016-01-02T00:01:00","guid":{"rendered":"https:\/\/blogs.technet.microsoft.com\/heyscriptingguy\/2016\/01\/02\/learn-easier-way-to-build-command-for-powershell-exe\/"},"modified":"2019-02-18T09:20:27","modified_gmt":"2019-02-18T16:20:27","slug":"learn-easier-way-to-build-command-for-powershell-exe","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/scripting\/learn-easier-way-to-build-command-for-powershell-exe\/","title":{"rendered":"Learn Easier Way to Build Command for PowerShell.exe"},"content":{"rendered":"

Summary<\/b>: Learn how to parse a here-string with Windows PowerShell.<\/p>\n

Honorary Scripting Guy, Sean Kearney, is here to show you a neat little trick.<\/p>\n

Anyone who has ever scheduled a PowerShell task knows that if you want to launch a cmdlet directly in PowerShell, you would launch it like this:<\/p>\n

PowerShell.exe –ExecutionPolicy Bypass –command ‘Get-ChildItem’<\/p>\n

No challenge there. It also does not end there. You can add some down-right complex stuff in there, for example:<\/p>\n

PowerShell.exe –executionpolicy Bypass –command ‘Set-ExecutionPolicy Bypass;Import-Module DeployImage; New-WindowsPeImage’<\/p>\n

This is an example of something I was playing with in the DeployImage<\/b> module when launching PowerShell automatically.<\/p>\n

Then again, in many cases, a script would be much easier to run if you knew where the script actually was. The challenge I ran into was trying to put together really complex command while typing it in the parameter.<\/p>\n

Then it dawned on me, “Why not write it as a script to make sure it works?” Yeah, that was pretty obvious. But how would I flip it back to a command for the PowerShell.exe? This is where a here-string is perfect!<\/p>\n

Here I have an example of something that I was actually doing. I needed to take the following script and flip it to a command in the PowerShell.exe.<\/p>\n

Set-ExecutionPolicy -executionpolicy Bypass<\/p>\n

$USBDisk=(Get-Disk | Where-Object { $_.BusType -eq ‘USB’ -and ‘$_.IsActive’ })<\/p>\n

$DriveLetter=($USBDisk | Get-Partition).DriveLetter<\/p>\n

Set-Location ($DriveLetter+’:\\DeployImage\\’)<\/p>\n

Import-Module ($DriveLetter+’:\\DeployImage\\DeployImage.Psd1)’<\/p>\n

I then stored it as a here-string:<\/p>\n

$PowerShellScript=@’<\/p>\n

Set-ExecutionPolicy -executionpolicy Bypass<\/p>\n

$USBDisk=(Get-Disk | Where-Object { $_.BusType -eq ‘USB’ -and ‘$_.IsActive’ })<\/p>\n

$DriveLetter=($USBDisk | Get-Partition).DriveLetter<\/p>\n

Set-Location ($DriveLetter+’:\\DeployImage\\’)<\/p>\n

Import-Module ($DriveLetter+’:\\DeployImage\\DeployImage.Psd1)’<\/p>\n

‘@<\/p>\n

Now all we need is to find where each line terminates and switch it with a semicolon.<\/p>\n

We can examine each byte in the here-string in the following manner:<\/p>\n

[byte][char]($PowerShellScript)[10]<\/p>\n

We would eventually notice that two characters at the end of each line are:<\/p>\n