how to let function display one section - powershell

Question

teaching myself about functions - I have written the below and problem I have at the moment is this:
1.The output is displayed in a hash table like format - ie #{FileVersion=6.1.7601.18606; IsReadOnly?=False; Directory=C:\windows\system32}. Is there a way of not displaying it in this format?
2.For the IF statment how do I get the code to just look at the ProductVersion bit of the output and not the whole function...or is that the point of a function, should I just have a function that just gets the file version separatly?
clear
function fileversion {
param ([string]$fileToCheck)
$fileInput = Get-Item $fileToCheck
$versionCheck = $fileInput.VersionInfo.ProductVersion
$DirectoryOfFile = $fileInput.DirectoryName
$IsReadOnly = $fileInput.IsReadOnly
$obj = New-Object psobject
$obj | Add-Member NoteProperty FileVersion $versionCheck
$obj | Add-Member NoteProperty IsReadOnly? $IsReadOnly
$obj | Add-Member NoteProperty Directory $DirectoryOfFile
Write-host $obj
}
$firstFile = fileversion C:\windows\system32\lsasrv.dll
If ($versionCheck -eq '6.1.7601.18606')
{ Write-host "File for is $TRUE" }
Else
{ Write-Host $False }

Answer 1

Don't know why you need a function since in the end you are just using one property of the object returned. Still, if you need the function you can just simplify it.
function fileversion{
param ([string]$fileToCheck)
Get-Item $fileToCheck | Select-Object #{Label="FileVersion";Expression={$_.VersionInfo.ProductVersion}},
#{Label="IsReadOnly?";Expression={$_.IsReadOnly}},
#{Label="Directory";Expression={$_.DirectoryName}}
}
No need to create a new object when the current one already has what you need. We use calculated properties to create the property names you wanted.
By default all output from functions is returned to the output stream. By sending the $obj to Write-Host you were removing that data from the stream. The output you say was Write-host casting the entire object as a [string]
Simple If
You could have just done this as well depending on your needs. This way you dont need a custom function
$version = (Get-Item C:\windows\system32\lsasrv.dll).VersionInfo.ProductVersion
If($version -eq '6.1.7601.18606'){
write-host "Version match"
} Else {
write-host "$version does not match"
}
You could always change the file path to a variable. Again, this was just suggestion. Please do whatever makes your scripting life comfortable.

Answer 2

use Write-output instead of write-host and check the version using the right property name (FileVersion) on the returned object:
If ($firstFile.FileVersion -eq '6.1.7601.18606')
{ Write-host "File for is $TRUE" }
Else
{ Write-Host $False }

Answer 3

** Revised **
1.) 'IF' condition statement should be applied to the property before $obj is created.
2.) To make the function more flexible and reusable, you should expand on the parameter criteria to allow for values from pipeline and and array of values as input.
function fileversion {
param(
[Parameter(Mandatory=$True,
ValueFromPipeline=$True,
ValueFromPipelineByPropertyName=$True)]
[Alias('files')]
[string[]]$filesToCheck
)
$fileInput = Get-Item $filesToCheck
foreach($f in $fileInput) {
$properties = #{
'File'=Split-Path $f -Leaf;
'FileVersion'=$f.VersionInfo.ProductVersion;
'CorrectVersion'=IF($versionCheck -eq '6.1.7601.18606') {$TRUE } ELSE {$False };
'IsReadyOnly'=$f.IsReadOnly;
'DirectoryOfFile'=$f.DirectoryName
}
$obj = New-Object psobject -Property $properties
Write-Output $obj
}
}