Converting Custom Object arrays to String arrays in Powershell

Question

So I'm tweaking some Powershell libraries and I've a simple question that I'd like to solve in the best way.....

In short, I've some custom PSObjects in an array:

$m1 = New-Object PSObject –Property @{Option="1"; Title="m1"} $m2 = New-Object PSObject –Property @{Option="2"; Title="m2"} $m3 = New-Object PSObject –Property @{Option="3"; Title="m3"}  $ms = $m1,$m2,$m3 

that I wish to convert into a string array.... ideally a single string array which has an entry for each item with the properties concatenated. i.e.

"1m1", "2m2", "3m3"

I've tried $ms | Select-Object Option,Title and $ms | %{ "O: $_.Option T: $_.Title "} but they give me arrays of the PSObject (again) or arrays of arrays.

Answer 1

This will give you what you want:

$strArray = $ms | Foreach {"$($_.Option)$($_.Title)"} 

Select-Object is kind of like an SQL SELECT. It projects the selected properties onto a new object (pscustomobject in v1/v2 and Selected.<orignalTypeName> in V3). Your second approach doesn't work, because $_.Option in a string will only "interpolate" the variable $_. It won't evaluate the expression $_.Option.

You can get double-quoted strings to evaluate expressions by using subexpressions, for example, "$(...)" or "$($_.Option)".