PowerShell crashes on `if ( $? = $false )` - powershell

I'm playing with PowerShell and I've encountered a crash that I can easily reproduce on my computer.
I'm not sure if the code is correct. However, running the following piece makes powershell.exe and powershell_ise.exe crash. I guess that my use of if ( $? = $false ) is wrong, but crash should not happen in such case. Removing If statement helps to avoid the crash.
Is there anything I'm missing?
I'm running Windows 10 Pro and PowerShell 5.1.14393.206.
Update 1
OK, thanks to #Martin I know that I mistakenly used = instead of -eq. But why this crash happens?
Update 2
Filed a bug report to PowerShell UserVoice: https://windowsserver.uservoice.com/forums/301869-powershell/suggestions/16977433-assigning-a-value-to-false-crashes
Update 3
It seems to be a known bug: https://github.com/PowerShell/PowerShell/issues/2243 that should be fixed soon https://github.com/PowerShell/PowerShell/pull/2320
Test-Path "C:\test"
if ( $? = $false ) {
Out-Host "Hello World"
}
Fault bucket 127386360339, type 5
Event Name: PowerShell
Response: Not available
Cab Id: 0
Problem signature:
P1: powershell.exe
P2: 10.0.14393.206
P3: stem.Management.Automation.PSInvalidCast
P4: stem.Management.Automation.PSInvalidCast
P5: ation.LanguagePrimitives.ThrowInvalidCastException
P6: ation.LanguagePrimitives.ThrowInvalidCastException
P7: Pipeli..ution Thread
P8:
P9:
P10:

Your code is wrong. You are assigning $false to the question mark variable which is a read-only variable. You probably want to replace the = with -eq:
Test-Path "C:\test"
if ( $? -eq $false ) {
Out-Host "Hello World"
}

Related

AutomationFocusChangedEventHandler: event dose not triggerd in powershell

I'm traying to detect focus change using a powershell script, hier is my code
start calc
Write-Host "Loading MS UIA assemblies"
[void][System.Reflection.Assembly]::LoadWithPartialName("UIAutomationClient")
[void][System.Reflection.Assembly]::LoadWithPartialName("UIAutomationTypes")
[void][System.Reflection.Assembly]::LoadWithPartialName("UIAutomationProvider")
[void][System.Reflection.Assembly]::LoadWithPartialName("UIAutomationClientsideProviders")
try
{
# WORKAROUND: There is a weird bug: first call fails ...
[Windows.Automation.ClientSettings]::RegisterClientSideProviderAssembly([UIAutomationClientsideProviders.UIAutomationClientSideProviders].Assembly.GetName())
}
catch {}
# ... second call succeeds:
[Windows.Automation.ClientSettings]::RegisterClientSideProviderAssembly([UIAutomationClientsideProviders.UIAutomationClientSideProviders].Assembly.GetName())
$focusedElem = [Windows.Automation.AutomationElement]::FocusedElement #this one work fine
Write-Host "name: " $focusedElem.Current.Name
Write-Host "ControlType: " $focusedElem.Current.ControlType
Write-Host "ProcessId: " $focusedElem.Current.ProcessId
$onFocusChange = { # this dose not fired !!!!
param([Sytem.Object]$src, [Windows.Automation.AutomationFocusChangedEventArgs]$e)
start notepad
}
$focusChangeHandler = [Windows.Automation.AutomationFocusChangedEventHandler]($onFocusChange)
[Windows.Automation.Automation]::AddAutomationFocusChangedEventHandler($focusChangeHandler)
Start-Sleep -Seconds 5 #durring this sleep i change the focused window, but nothing happen :(
[Windows.Automation.Automation]:: RemoveAutomationFocusChangedEventHandler($focusChangeHandler)
any idea why this script not working, or any idea how to monitoring focus change in powershell without external tools ?

PowerShell - InvalidCastException when returning Boolean to explicitly declared variable [duplicate]

This question already has answers here:
Function return value in PowerShell
(10 answers)
Closed 5 years ago.
I've written a PowerShell script to perform some pre-installation setup for a series of patches I'm deploying to client computers across our estate and I'm hitting a bit of an odd issue that I can't wrap my head around.
The setup patch checks the 'C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe.config' file due to a "feature" of PowerShell 2.0 whereby the application uses .NET Framework 2.0.0 by default instead of 4.5.2, preventing certain functions from being executed. If the file doesn't exist or the evaluated values don't match a specification, I add the XML file and provide the necessary values.
The command I run is as follows:
$psConfigDir = "C:\Windows\System32\WindowsPowerShell\v1.0"
$psConfigFileName = "powershell.exe.config"
[boolean]$psExeXml = Set-PSRuntimeConfigs -FilePath ( [String]::Format("{0}\{1}", $psConfigDir, $psConfigFileName) ) -CLRVersions #("v4.0.30319", "v2.0.50727")
...and the Set-PSRuntimeConfigs method is found in a PowerShell Module I created with the code below:
Function Set-PSRuntimeConfigs {
[CmdletBinding()]
Param(
[String]$FilePath,
[System.Collections.ArrayList]$CLRVersions
)
Try {
$xmlWriter = New-Object System.Xml.XmlTextWriter($FilePath, $null)
$xmlWriter.Formatting = "Indented"
$xmlWriter.Indentation = 4
$xmlWriter.WriteStartDocument()
$xmlWriter.WriteStartElement("configuration")
$xmlWriter.WriteStartElement("startup")
$xmlWriter.WriteAttributeString("useLegacyV2RuntimeActivationPolicy", $true)
$CLRVersions | ForEach-Object {
$xmlWriter.WriteStartElement("supportedRuntime")
$xmlWriter.WriteAttributeString("version", $_)
$xmlWriter.WriteEndElement()
}
$xmlWriter.WriteEndElement()
$xmlWriter.WriteEndElement()
$xmlWriter.WriteEndDocument()
$xmlWriter.Close()
$xmlWriter.Dispose()
return $true
} Catch {
echo "ERROR: Exception occurred during XML write process!"
echo "ERROR: Exception message: $($_.Exception.Message)"
return $false
}
}
However, the function is returning an InvalidCastException when trying to assign the result of the function to the $psExeXml variable. Oddly, PowerShell returns with an error stating that [System.Object()] cannot be converted to type [Boolean] despite the fact that only $true or $false is returned from the function.
My first thought is that an exception was being thrown by the function due to a code issue but the function is written to report the error in the prompt and just return $false in that case... Regardless, I'm stuck and can't figure out where to proceed with this...
If the function produces any output then the result will be an array containing the strings that were output and then the final element will be your boolean.
So for this code:
echo "ERROR: Exception occurred during XML write process!"
echo "ERROR: Exception message: $($_.Exception.Message)"
return $false
the function returns an array of two strings and a boolean.

F# Run Powershell Script As Target

Trying to run a powershell script using F# FAKE but nothing happens... there are no errors, the target loads but nothing actually is run.
// include Fake lib
#r "packages/FAKE/tools/FakeLib.dll"
#r "System.Management.Automation"
open System
open System.IO
open System.Diagnostics
open System.Management.Automation
Target "Powershell" <| fun _ ->
PowerShell.Create()
.AddScript("& 'build-database.ps1'")
.AddParameter("BuildVersion", version)
.AddParameter("Debug", "")
.Invoke()
|> Seq.iter (printfn "%O")
// Dependencies
"Clean"
==> "Powershell"
// start build
RunTargetOrDefault "Powershell"
Am I missing something? Without any error I am not sure what the issue is.
* Updated *
This is the powershell script I am testing with, FAKE does nothing.
New-Item c:\AnEmptyFile.txt -ItemType file
I finally figured out another way to do it that works. In case someone else has the need to call a powershell script from within F# FAKE the following method worked for me.
Target "Powershell" (fun _ ->
let p = new System.Diagnostics.Process();
p.StartInfo.FileName <- "cmd.exe";
p.StartInfo.Arguments <- ("/c powershell -ExecutionPolicy Unrestricted .\\script.ps1)
p.StartInfo.RedirectStandardOutput <- true
p.StartInfo.UseShellExecute <- false
p.Start() |> ignore
printfn "Processing..."
printfn "%A" (p.StandardOutput.ReadToEnd())
printfn "Finished"
)
Its possible to use Shell.Execute and invoke powershell.exe:
Target "ImportDb" (fun _ ->
Shell.Exec("powershell.exe", "-NoProfile -ExecutionPolicy Bypass -File script.ps1") |> ignore)

Hash entry sometime is $NULL (error), and sometimes isn't?

I have my little 3-sided socket-server. Each server has its own hash with its key-values.
The very first is:
$Local = #{ID="Local"; ...}
$RemtA = #{ID="RemtA"; ...}
$RemtB = #{ID="RemtB"; ...}
I start for all of the the listeners - no problem.
If now a client wants to connect, I want to add the ID to $ProgressHead, which is defined like this:
$ProgressHead = "Value-Broadcast, Connected: "
and used in my function to accept a client called with its hash as $h:
if ( !$h.Connected ) {
#Write-Host "$($h.ID) not connected, pending: $($h.listener.Pending())"
if ( $h.listener.Pending()) {
$h.client = $h.listener.AcceptTcpClient() # will block here until connection
$h.stream = $h.client.GetStream();
$h.writer = New-Object System.IO.StreamWriter $h.stream
$h.writer.AutoFlush = $true
$h.Connected = $true
Write-Host $Global:ProgressHead # fails - empty ??
Write-Host $h.ID # prints oh depit it is marked as error
if ( !$Global:ProgressHead.Contains( $h.ID ) ) { # <= HERE IS THE ERROR ????
$Global:ProgressHead= "$($Global:ProgressHead)$($h.ID) "
}
}
}
The Error message says:
Can't call a method for an expression which is NULL and $h.ID is underlined
BUT I DO NOT get any error if I start this either in the cmd-console when running powershell -file ThreeServer.ps1 or within the ISE in debug mode. The ID is written correctly to $ProgressHead!
Only if I start this in the Powershell console (PS C:\...> ./ThreeServer.ps1) I get this error, but all the other keys in the lines above are valid ONLY $h.ID on ONLY the PS-console throws this error?

PowerShell webdeploy

I'm trying to use PowerShell with web deployment based on this
article
This is how my script looks like
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.Web.Deployment")
function Sync-Provider($provider, $sourceLocation, $destLocation)
{
$destBaseOptions = new-object Microsoft.Web.Deployment.DeploymentBaseOptions
$syncOptions = new-object Microsoft.Web.Deployment.DeploymentSyncOptions
Try
{
$deploymentObject = [Microsoft.Web.Deployment.DeploymentManager]::CreateObject($provider, $sourceLocation)
$deploymentObject.SyncTo($provider,$destLocation,$destBaseOptions,$syncOptions)
}
Catch
{
echo "EXCEPTION THROWN::[ $_ ] "
#throw $_
}
}
Sync-Provider ("apphostConfig","D:\NerdDinner_2.0\NerdDinner","c:\inetpub\wwwroot")
Running this gives the following exception
EXCEPTION THROWN::[ Cannot convert argument "0", with value: "System.Object[]",
for "CreateObject" to type "Microsoft.Web.Deployment.DeploymentWellKnownProvid
er": "Cannot convert value "apphostConfig,D:\NerdDinner_2.0\Ne
rdDinner,c:\inetpub\wwwroot" to type "Microsoft.Web.Deployment.DeploymentWellKn
ownProvider" due to invalid enumeration values. Specify one of the following en
umeration values and try again. The possible enumeration values are "Unknown, A
ppHostConfig, AppHostSchema, AppPoolConfig, ArchiveDir, Auto, Cert, ComObject32
, ComObject64, ContentPath, CreateApp, DirPath, DBFullSql, DBMySql, FilePath, G
acAssembly, IisApp, MachineConfig32, MachineConfig64, Manifest, MetaKey, Packag
e, RecycleApp, RegKey, RegValue, RootWebConfig32, RootWebConfig64, RunCommand,
SetAcl, WebServer, WebServer60"." ]
Could you give me some hints on this, please?
Try to enclose the first parameter [Microsoft.Web.Deployment]::DeploymentWellKnownProvider.AppHostConfig with a pair of extra parenthesis: ([Microsoft.Web.Deployment]::DeploymentWellKnownProvider.AppHostConfig).
In my case I had the same problem, just opened the powershell console as Administrator and it worked.