Vista - Working om directories

I'm writing a script to archive data files from a directory more than 30 days
old and delete the directory. Here's the script:
# Archive_Vis_Data.ps1
# Archive Visualizer data in the "Daily Data Analysis" directory

# Step 1: set the starting location
SL "C:\WindowsPowerShell\PerfMon Web\Daily Data Analysis"

# Step 2: calculate the date 30 days ago
$Monthago = ( get-date ).AddDays(-30).ToString('MMddyyyy')

# Step 3: Read the "MonitoredSystems.txt" file to get a list of data
directories.
#Read a new dir for each group of monitored systems
$Systems = Get-Content "C:\WindowsPowerShell\PS_Scripts\MonitoredSystems.txt"

# Step 4: Recursively CD to each dir. Then test for directories more than 30
days old.
Foreach ($System in $Systems)
{$DataDirs = Get-ChildItem | Select-Object FullName
ForEach($DataDir in $DataDirs)
{CD $DataDir
If ($DataDir.CreationTime.ToString('MMddyyyy') -gt $Monthago)
# Step 5: Test for the "combine_out" dir.
{$VisDirs = Get-ChildItem | Select-Object Name
# If the vis dir exists exists, CD to it.
If($VisDir.Name -eq "combine-out")
{$VisDir = "C:\WindowsPowerShell\PerfMon Web\Daily Data Analysis\" +
$System + $DataDir + "combine-out"
CD "combine-out"

# Step 6: Get the vis file name.
$FileNames = Get-ChildItem | Select-Object Name
$VisFile = (Get-ChildItem *.vis).Name

# Step 7: If $VisFile not null move the file to an archive dir with the
same name.
If ($VisFile -ne "")
# Create the archive dir.
{$ArcDir = 'C:\WindowsPowerShell\PerfMon Web\Archive\' + $System
SL $ArcDir
MkDir $Monthago
$ArcDir = $ArcDir + "\" + $Monthago

# Move the *.vis file.
Move-Item $VisFile -Destination $ArcDir
}
}
}
# Step 8: remove the original data dir.
rmdir $DataDir
}
}

# Return to the default dir
SL 'C:\WindowsPowerShell\PerfMon Web\Daily Data Analysis'

In step four the statement reading the subdirectories isn't working as
expected. It works at the command line but not in the script. The value of
$DataDirs is null and that generates an error in the comparison two lines
down. Suggestions?

I'm not sure if it's what's producing the results you're getting, but doing
doing that kind of date calculation on string data in mmddyyyy format is not
going to deal with data that crosses a year boundary very well.

"tERRY" wrote: