PowerShell: how to capture (or suppress) write-host

Question

I have a script call "a.ps1":

write-host "hello host"
"output object"

I want to call the script and obtain the output object, but I also want the standard output to be suppressed:

$result = .\a.ps1
# Don't want anything printed to the console here

Any hint?

Answer 1

There really is no easy way to do this.

A workaround is to override the default behavior of Write-Host by defining a function with the same name:

function global:Write-Host() {}

This is very flexible. And it works for my simplistic example above. However, for some unknown reason, it doesn't work for the real case where I wanted to apply (maybe because the called script is signed and for security reasons it doesn't allow caller to arbitrarily change the behavior).

Another way I tried was to modify the underlying Console's stdout by:

$stringWriter = New-Object System.IO.StringWriter
[System.Console]::SetOut($stringWriter)
[System.Console]::WriteLine("HI") # Outputs to $stringWriter
Write-Host("HI") # STILL OUTPUTS TO HOST :(

But as you can see, it still doesn't work.