Powershell 7 Debugging Secret

Erick — Sat, 18 Jul 2020 23:57:10 +0000

Powershell 7 introduced a new feature that not many people on the internet seem to know yet.
I'm talking about -ErrorAction mode Break

This new error action mode allows you to start a debugging session at the time a script reaches an error. Sounds easy right? Let's try it out!

Disclaimer: I usually haven't use the debugger, I'm one of those that usually start running commands one by one on the console to see where the code breaks 😅. But I think its time to grow up and start debugging like a pro and this new feature makes debugging a lot easier!

First, let's create a function that will have an error which we will need to fix.

function Divide-function{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory)]
        [int]
        $Number
    )
    process{
        return $Number/0 
    }
}

We will save our function in a Divide-function.ps1 file and open a Powershell session and dot source it . ./Divide-function.ps1

Then we run our function for the first time and let's we what happens

PS> Divide-Function 2
RuntimeException: C:\Scripts\Divide-Function.ps1:9
Line |
   9 |          return $Number/0
     |                 ~~~~~~~~~
     | Attempted to divide by zero.

WOW an ERROR! Now let's try to debug it

PS> Divide-Function 2 -ErrorAction Break
Entering debug mode. Use h or ? for help.

At C:\Scripts\Divide-Function.ps1:9 char:16
+         return $Number/0
+                ~~~~~~~~~

Easy as that, now we are debugging exactly where our code failed!

You can use this opportunity to explore the debugger on your own from here. I advise you to start with the PowerShell advice and use h or ? for help.


 s, stepInto         Single step (step into functions, scripts, etc.)
 v, stepOver         Step to next statement (step over functions, scripts, etc.)
 o, stepOut          Step out of the current function, script, etc.

 c, continue         Continue operation
 q, quit             Stop operation and exit the debugger
 d, detach           Continue operation and detach the debugger.

 k, Get-PSCallStack Display call stack

 l, list             List source code for the current script.
                     Use "list" to start from the current line, "list <m>"
                     to start from line <m>, and "list <m> <n>" to list <n>
                     lines starting from line <m>

 <enter>             Repeat last command if it was stepInto, stepOver or list

Do you want to know more about PowerShell Debugger: about_Debuggers

The Unknown Powershell Cmdlets Everyone Should Know About

Erick — Fri, 22 Nov 2019 21:56:43 +0000

Have you ever thought...I wish I have known this earlier!? With PowerShell, it is pretty common not to be aware of some of the features or options it has. It takes the time to read the documentation and at the time you (I) find a way to do X, you (I) will probably skip reading the documentation.
However, across experience and seeing others code, I have found some cmdlets, I wish I have known before! and it seems not everybody knows about them!
Today, I want to share these little secrets that have made my Powershell time a lot more enjoyable and hopefully make your life a bit easier.

Show-Command

Show-Command Set-Content

Yes...that's right! Now you have auto-generated GUI for any cmdlet you want, even the ones from custom modules! This comes pretty handily with some of the cmdlets you are not used to.

When you click "run", it actually copies the GUI inputs to your command line! So you can just copy and paste the code to a script if needed.

Set-Content -Path test.txt -Value HelloWorld

If you need extra help with the parameters or the cmdlet click the "?" button at the top right corner to get some extra help!

Get-Help -ShowWindow

Get-Help Get-Process -ShowWindow

If you use PowerShell you must know about the get-help command, but some people don't know it has a parameter flag call -ShowWindow.
This is pretty handy to get the full help of command, get search bar and even Zoom! (sometimes PS font-size is too small when I'm tired).

Out-GridView

Get-Process | Out-GridView

Sometimes you are working with a LOT of data, and maybe you want do to a manual quick scan and filtering before writing the next piece of code. Well, Out-GridView will help you through just that!

Invoke-Item

# You can also do "ii ." for short
Invoke-Item .

You just got an explorer window on your current path!

What's Next?

Now you have a new few tools to play in Powershell! I encourage you to keep exploring PowerShell, get-help with some * here and there is a great way to find out new things. Hope you enjoy this post, See you next time!