Flatten out multiple PowerShell arrays

Question

We have PowerShell objects that contain PSCustomObjects in the form of an array. To export this information to a text or Excel file we need to be able to flatten the data.

Example code:

$Fruits = [PSCustomObject]@{
    Name   = 'Banana'
    Colors = [PSCustomObject]@{
                Name = 'Green'
            },
            [PSCustomObject]@{
                Name = 'Yellow'
            }
    Taste = [PSCustomObject]@{
                Name = 'Good'
            },
            [PSCustomObject]@{
                Name = 'Bad'
            },
            [PSCustomObject]@{
                Name = 'Awful'
            }
}

Generates:

$Fruits | fl *

Name   : Banana
Colors : {@{Name=Green}, @{Name=Yellow}}
Taste  : {@{Name=Good}, @{Name=Bad}, @{Name=Awful}}

To be able to have a clean export, the desired result should be something like this:

Name    |   Color    |    Taste
----    |   -----    |    -----
Banana  |   Yellow   |    Good
Banana  |   Green    |    Bad
Banana  |            |    Awful

How is it possible to unravel this object?

I know everything about fruit these days, that's why I left out the pears ;) But a brown banana.. I'd still take it! :D — DarkLite1
– DarkLite1, Commented May 2, 2016 at 11:53

Frode F. · Accepted Answer · 2016-05-02 15:10:16Z

2

You would need to find the column with the most values and use that as the limit for a for-/while-loop. Ex.

$maxLines = $Fruits.psobject.Properties | Where-Object { $_.TypeNameOfValue -match 'Object\[\]|ICollection' } | Foreach-Object { $_.Value.Count } | Sort-Object -Descending | Select-Object -First 1
0..($maxLines-1) | ForEach-Object {
    New-Object psobject -Property @{
        Name = $Fruits.Name
        Color = $Fruits.Colors[$_] | Foreach-Object { $_.Name }
        Taste = $Fruits.Taste[$_] | Foreach-Object { $_.Name }
    }
} | Select-Object Name, Color, Taste

Output:

Name   Color  Taste
----   -----  -----
Banana Green  Good 
Banana Yellow Bad  
Banana        Awful

edited May 2, 2016 at 15:10

answered May 2, 2016 at 10:25

Frode F.

55.4k9 gold badges104 silver badges118 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

DarkLite1 Over a year ago

Thank you Frode, this was exactly what I was looking for.

DarkLite1 Over a year ago

Only thing I improved was: Taste = if ($R.Taste | Select-Object -Index $_) {$R.Taste [$_] | Select-Object -ExpandProperty Name}; to avoid errors when nothing is available.

Frode F. Over a year ago

It should work fine in PS 3.0+ I think (tested on PS5), but in PS2 it would fail. There was also a bug with detecting the array-columns in PS2, so I've updated the answer to fix both.

Collectives™ on Stack Overflow

Flatten out multiple PowerShell arrays

1 Answer 1

3 Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Linked

Related