Foreach loop not reading files in numeric order

Question

I have below files which i am reading using a foreach loop.

$GetGeneratedFiles = Get-ChildItem -Path "C:\Script\LF*.csv" -recurse |  % { $_.FullName }

C:\Script\LF_Batch_1.csv
C:\Script\LF_Batch_10.csv
C:\Script\LF_Batch_11.csv
C:\Script\LF_Batch_12.csv
C:\Script\LF_Batch_13.csv
C:\Script\LF_Batch_14.csv
C:\Script\LF_Batch_15.csv
C:\Script\LF_Batch_16.csv
C:\Script\LF_Batch_17.csv
C:\Script\LF_Batch_18.csv
C:\Script\LF_Batch_19.csv
C:\Script\LF_Batch_2.csv
C:\Script\LF_Batch_20.csv
C:\Script\LF_Batch_21.csv etc...upto LF_Batch_.96.csv

Problem is it is reading the files like above not 1,2,3...and so on.

Please need idea how to read in ordered way

You've encountered classical natural order vs ASCIIbetical order issue. Check out this [earlier answer](https://stackoverflow.com/q/5427506/503046) about the same. — vonPryz, Sep 17 '20 at 12:02

score 1 · Answer 1 · answered Sep 17 '20 at 12:04

Solved using below approach

        $GetGeneratedFiles = Get-ChildItem -Path "C:\Script\LF*.csv" -recurse |  % { $_.FullName }

        $ToNatural = { [regex]::Replace($_, '\d+', { $args[0].Value.PadLeft(20) }) }
        
        $GetGeneratedFiles = $GetGeneratedFiles | Sort-Object $ToNatural

Thanks @vonPryz for the reference.

js2010 · Answer 2 · 2020-09-17T14:26:59.870

Another way. It's funny how I just did another answer similar to this. A numeric sort on the names.

echo hi | set-content (1,2,10,20 | % tostring LF_Batch_0\.csv)
dir | sort {[void]($_ -match '\d+'); [int]$matches.0}


    Directory: C:\Users\js\foo

Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
-a---           9/17/2020  9:14 AM              4 LF_Batch_1.csv
-a---           9/17/2020  9:14 AM              4 LF_Batch_2.csv
-a---           9/17/2020  9:14 AM              4 LF_Batch_10.csv
-a---           9/17/2020  9:14 AM              4 LF_Batch_20.csv

Foreach loop not reading files in numeric order

2 Answers2