Newbie powershell argument issues-CodePudding

I made powershell script that [1] accepts 2 arguments (aka parameters), [2] changes a file's modified date & time, and [3] writes something to host. The following command line works just fine in the powershell console, but triggers an error message when I run the same command line in a Windows cmd prompt (DOS) Window:

E:\Apps\UtilitiesByMarc\Change_DateTime_for_test1.bat_and_Hello_world_with_2_named_args_aaa.ps1 -dateTimeVarArg "01/11/2005 06:01:36" -file_dateTimeMod_fullname "E:\Apps\Delete01\test1.bat"

The following is the coding for the powershell script to which I gave the long name, 'Change_DateTime_for_test1.bat_and_Hello_world_with_2_named_args_aaa.ps1':

param ( [string]$dateTimeVarArg,  [string]$file_dateTimeMod_fullname)
Get-ChildItem  $file_dateTimeMod_fullname | % {$_.LastWriteTime = $dateTimeVarArg}
#Get-ChildItem  "E:\Apps\Delete01\test1.bat" | % {$_.LastWriteTime = $dateTimeVarArg}
$strString = "Hello World"
write-host $strString


function ftest{
$test = "Test"
write-host $test
}

ftest

When I run the command line shown above in a Windows DOS command prompt setting, I get the following error message:

Exception setting "LastWriteTime": "Cannot convert null to type "System.DateTime"."
At E:\Apps\UtilitiesByMarc\Change_DateTime_for_test1.bat_and_Hello_world_with_1_named_arg_aaa.ps1:6 char:50
  ... "E:\Apps\Delete01\test1.bat" | % {$_.LastWriteTime = $dateTimeVarArg}
                                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      CategoryInfo          : NotSpecified: (:) [], SetValueInvocationException
      FullyQualifiedErrorId : ExceptionWhenSetting

I would like to know [1] how to alter the command line shown above (which works fine in the powershell console) so that it works in a Windows DOS command prompt setting, and [2] where I can learn more about why my command line triggers errors, and how to avoid them.
According to the output from the command "Get-Host | Select-Object Version", I am running version. 5.1.19041.1682.

Any tips would be much appreciated.

CodePudding user response：

By default, you can not directly execute PowerShell scripts (.ps1 files) from cmd.exe, the Windows legacy shell, or from outside PowerShell altogether.

Attempting to do so opens the script file for editing instead, as does double-clicking .ps1 files from File Explorer / the desktop.

Executing .ps1 scripts from outside PowerShell itself requires use of the PowerShell CLI (powershell.exe for Windows PowerShell, pwsh for PowerShell (Core) 7 ), which in your case translates to a call such as (additional CLI parameters may be called for):

powershell.exe -File E:\Apps\UtilitiesByMarc\Change_DateTime_for_test1.bat_and_Hello_world_with_2_named_args_aaa.ps1 -dateTimeVarArg "01/11/2005 06:01:36" -file_dateTimeMod_fullname "E:\Apps\Delete01\test1.bat"

As for what you tried:

The fact that you were able to execute your .ps1 from cmd.exe suggests that you changed the file-type definition for such files to execute via powershell.exe instead.

The fact that the arguments you tried to pass to the script were ignored - as implied by the error message you got - suggests that you used File Explorer's Open with shortcut-menu command to choose to open all .ps1 files with powershell.exe; said method does not support argument-passing.

There is a way to change the file-type definition to support argument-passing too, and it is detailed in this answer (section "Programmatic method").

Generally, however, I suggest not applying this customization, especially in batch files that must also be run by other users / on other machines, which cannot be expected to have the same customization in place.