Conditional Logic and Casting in Powershell - powershell

Question

I'm creating a script that imports 2 columns of CSV data, sorts by one column cast as type int, and shows only the values between 0 and 10,000. I've been able to get up to the sorting part, and I am able to show only greater than 0. When I try to add "-and -lt 10000" various ways, I am unable to get any useful data. One attempt gave me the data as if it were string again, though.
This only gives me > 0 but sorts as type int. Half way there!:
PS C:\> $_ = Import-Csv .\vc2.csv | Select -Property User_Name, Minutes; $_ | Sort {[int] $_.Minutes} | Where {($_.Minutes -gt 0)}
This gives me 10000 > x > 0 but sorts as string:
PS C:\> $_ = Import-Csv .\vc.csv | Select -Property User_Name, Minutes; $_ | Sort {[int] $_.Minutes} | Where {($_.Minutes -gt 0) -and ($_.Minutes -lt 10)}
Here and here are where I tried recasting as int and it gave me many errors:
PS C:\> $_ = Import-Csv .\vc.csv | Select -Property User_Name, Minutes; $_ | Sort {[int] $_.Minutes} | Where {[int]{($_.Minutes -gt 0) -and ($_.Minutes -lt 10000)}}
PS C:\> $_ = Import-Csv .\vc.csv | Select -Property User_Name, Minutes; $_ | Sort {[int] $_.Minutes} | Where { ({[int]$_.Minutes} -gt 0) -and ({[int]$_.Minutes} -lt 10000) }
Error: Cannot convert the "($.Minutes -gt 0) -and ($.Minutes -lt 10000)" value of type "System.Management.Automation.ScriptBlock" to type "System.Int32".
What is the proper syntax for this?

Answer 1

PowerShell usually coerces arguments of binary operators to the type of the left operand. This means when doing $_.Minutes -gt 10 the 10 gets converted to a string, because the fields in a parsed CSV are always strings. You can either switch the operands around: 10 -lt $_.Minutes or add a cast: [int]$_.Minutes -gt 10 or +$_.Minutes -gt 10.
Usually, when dealing with CSVs that contain non-string data that I want to use as such, I tend to just add a post-processing step, e.g.:
Import-Csv ... | ForEach-Object {
$_.Minutes = [int]$_.Minutes
$_.Date = [datetime]$_.Date
...
}
Afterwards the data is much nicer to handle, without excessive casts and conversions.

Answer 2

The problem is the use of the { and } brackets in the Where statement. Those are being interpreted as script blocks.
Where { ({[int]$_.Minutes} -gt 0) -and ({[int]$_.Minutes} -lt 10000) }
Try using ( and ) or excluding them altogether.
Where { (([int]$_.Minutes) -gt 0) -and (([int]$_.Minutes) -lt 10000) }
The way you're assigning values to $_ is also weird.

Answer 3

$_ represents the current value in the pipeline.
$list = #(1,2,3)
$list | foreach { $_ }
1
2
3
by assigning "$_" a value, you are losing that value as soon as you place it in the pipeline.
try something like:
$mycsv = import-csv .\vc.csv; $mycsv | select ...etc