Capturing Output

There are several ways to capture the output of commands in PowerShell, as listed in Table A-16.

Table A-16. Capturing output in PowerShell
Command	Result
`$variable` `=` `Command`	Stores the objects produced by the PowerShell command into `$variable`.
`$variable` `=` `Command` `\| Out-String`	Stores the visual representation of the PowerShell command into `$variable`. This is the PowerShell command after it’s been converted to human-readable output.
`$variable` `=` `NativeCommand`	Stores the (string) output of the native command into `$variable`. PowerShell stores this as a list of strings—one for each line of output from the native command.
`Command` `-OutVariable` `variable`	For most commands, stores the objects produced by the PowerShell command into `$variable`. The parameter `-OutVariable` can also be written `-Ov`.
`Command` `>` `File`	Redirects the visual representation of the PowerShell (or standard output of a native command) into `File`, overwriting `File` if it exists. Errors are not captured by this redirection.
`Command` `>>` `File`	Redirects the visual representation of the PowerShell (or standard output of a native command) into `File`, appending to `File` if it exists. Errors are not captured by this redirection.
`Command` `2>` `File`	Redirects the errors from the PowerShell or native command into `File`, overwriting `File` if it exists.
`Command` `n>``File`	Redirects stream number `n` into `File`, overwriting `File` if it exists. Supported streams are `2` for error, `3` for warning, `4` for verbose, `5` for debug, `6` for the structured information stream, and `*` for all.
`Command` `2>>` `File`	Redirects the errors from the PowerShell or native command into `File`, appending to `File` if it exists.
`Command` `n>>` `File`	Redirects stream number `n` into `File`, appending to `File` if it exists. Supported streams are `2` for error, `3` for warning, `4` for verbose, `5` for debug, `6` for the structured information stream, and `*` for all.
`Command` `>` `File` `2>&1`	Redirects both the error and standard output streams of the PowerShell or native command into `File`, overwriting `File` if it exists.
`Command` `>>` `File` `2>&1`	Redirects both the error and standard output streams of the PowerShell or native command into `File`, appending to `File` if it exists.

While output from the Write-Host cmdlet normally goes directly to the screen, you can use the structured information stream to capture it into a variable:

PS > function HostWriter { Write-Host "Console Output" }
PS > $a = HostWriter
Console Output
PS > $a
PS > $a = HostWriter 6>&1
PS > $a
Console Output