Output echo a variable to a text file

Question

I m running a PowerShell script against many servers  and it is logging output to a text file   I d like to capture the server the script is currently running on  So far I have    file      server share file txt   computername    env computername   computername   Add-Content -Path  file   This last line adds question marks in the output file  Oops   How do I output a variable to a text file in PowerShell

User · Answer

The simplest Hello World example      hello    Hello World   hello   Out-File c  debug txt

User · Answer

After some trial and error  I found that   computername    env computername   works to get a computer name  but sending  computername to a file via Add-Content doesn t work   I also tried  computername Value   Instead  if I use   computername   get-content env computername   I can send it to a text file using   computername   Out-File  file

User · Answer

Note  The answer below is written from the perspective of Windows PowerShell  However  it applies to the cross-platform PowerShell Core edition  v6   as well  except that the latter - commendably - consistently defaults to BOM-less UTF-8 character encoding  which is the most widely compatible one across platforms and cultures    To complement bigtv s helpful answer helpful answer with a more concise alternative and background information     gt   file is effectively the same as   Out-File  file   Objects are written the same way they display in the console    Default character encoding is UTF-16LE  mostly 2 bytes per char    with BOM    Use Out-File -Encoding  lt name gt  to change the encoding   env computername  gt   file    Set-Content calls  ToString   on each object to output    Default character encoding is  quot ANSI quot   culture-specific  single-byte     Use Set-Content -Encoding  lt name gt  to change the encoding    Use Set-Content rather than Add-Content  the latter is for  appending  to a file   env computername   Set-Content  file    When outputting to a text file  you have 2 fundamental choices that use different object representations and  in Windows PowerShell  as opposed to PowerShell Core   also employ different default character encodings   Out-File  or  gt     Out-File -Append  or  gt  gt     Suitable for output objects of any type  because PowerShell s default output formatting is applied to the output objects   In other words  you get the same output as when printing to the console    The default encoding  which can be changed with the -Encoding parameter  is Unicode  which is UTF-16LE in which most characters are encoded as 2 bytes  The advantage of a Unicode encoding such as UTF-16LE is that it is a global alphabet  capable of encoding all characters from all human languages   In PSv5 1   you can change the encoding used by  gt  and  gt  gt   via the  PSDefaultParameterValues preference variable  taking advantage of the fact that  gt  and  gt  gt  are now effectively aliases of Out-File and Out-File -Append  To change to UTF-8  for instance  use   PSDefaultParameterValues  Out-File Encoding    UTF8      Set-Content   Add-Content   For writing strings and instances of types known to have meaningful string representations  such as the  NET primitive data types  Booleans  integers          psobject ToString   method is called on each output object  which results in meaningless representations for types that don t explicitly implement a meaningful representation   hashtable  instances are an example     one   1     Set-Content t txt writes literal System Collections Hashtable to t txt  which is the result of    one   1   ToString      The default encoding  which can be changed with the -Encoding parameter  is Default  which is the system s  quot ANSI quot  code page  a the single-byte culture-specific legacy encoding for non-Unicode applications  most commonly Windows-1252  Note that the documentation currently incorrectly claims that ASCII is the default encoding   Note that Add-Content s purpose is to append content to an existing file  and it is only equivalent to Set-Content if the target file doesn t exist yet  Furthermore  the default or specified encoding is blindly applied  irrespective of the file s existing contents  encoding      Out-File    gt    Set-Content   Add-Content all act culture-sensitively  i e   they produce representations suitable for the current culture  locale   if available  though custom formatting data is free to define its own  culture-invariant representation - see Get-Help about format ps1xml   This contrasts with PowerShell s string expansion  string interpolation in double-quoted strings   which is culture-invariant - see this answer of mine  As for performance  Since Set-Content doesn t have to apply default formatting to its input  it performs better   As for the OP s symptom with Add-Content  Since  env COMPUTERNAME cannot contain non-ASCII characters  Add-Content s output  using  quot ANSI quot  encoding  should not result in   characters in the output  and the likeliest explanation is that the   were part of the preexisting content in output file  file  which Add-Content appended to

User · Answer

Your sample code seems to be OK  Thus  the root problem needs to be dug up somehow  Let s eliminate chance for typos in the script  First off  make sure you put Set-Strictmode -Version 2 0 in the beginning of your script  This will help you to catch misspelled variable names  Like so     Test ps1 set-strictmode -version 2 0   Comment this line and no error will be reported   foo    bar  set-content -path   test txt -value  fo   Error  Should be   foo   PS C  temp gt    test ps1 The variable   fo  cannot be retrieved because it has not been set  At C  temp test ps1 3 char 40   set-content -path   test txt -value  fo  lt  lt  lt  lt        CategoryInfo            InvalidOperation   fo Token      RuntimeException       FullyQualifiedErrorId   VariableIsUndefined   The next part about question marks sounds like you have a problem with Unicode  What s the output when you type the file with Powershell like so    file      server share file txt  cat  file

User · Answer

Here is an easy one    myVar  gt   c  myfilepath myfilename myextension    You can also try   Get-content  c  someOtherPath someOtherFile myextension   gt   c  myfilepath myfilename myextension

[powershell] Output ("echo") a variable to a text file

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