Update CSV column using Powershell - powershell

Question

I have CSV1 (as below) where I have to populate the last column from CSV 2 given below..
CSV1
Computer Product Code Country Department LaptopDesktop
-------- ------- ---- ------- ---------- -------------
Com1 EliteDesk 705 HP2190 AU FN
Com2 EliteBook 830 HP1023 AU IT
Com3 EliteBook 830 HP1023 FR FN
Com4 Zbook 15U HP2020 IN FN
Com5 OptiPlex 3010 DL1721 FR FN
CSV2
Product Type Code
------- ---- ----
EliteBook 1030 L HP1020
EliteBook 1040 L HP1021
EliteBook 830 L HP1023
Zbook 15U L HP2020
EliteDesk 800 D HP3035
EliteDesk 705 D HP2190
Thinkpad L480 L LE990
OptiPlex 3010 D DL1721
with below code, I'm unable to update 'LaptopDesktop' column in CSV1 whereas output gets appended with -Append parameter or without that, it just overwrite the whole CSV.....How do I fix this?
{
$SystemData =#()
$Productinfo = Import-Csv "C:\CSV2.csv"
$Mastercsv = Import-Csv "C:\CSV1.csv"
foreach($record in $Mastercsv)
{
$mcode = $($record.code)
$mDLtype = $($record.LaptopDesktop)
$SysType = ($Productinfo | where {$_.code -eq $mcode}).type
if ($SysType -eq $null)
{
$sysType = 'Unknown, due to non-matching code'
}
$AddsysType=New-Object PSCustomObject
Add-Member -InputObject $AddsysType -membertype noteproperty -name "LaptopDesktop" -value $sysType
$SystemData +=$AddsysType
}Return, $SystemData
}
$DeviceType= Update-SystemType
$DeviceType| Export-Csv 'C:\CSV1.csv' -Force -NoTypeInformation

Answer 1

I think the fact you've just opened the file to import then try to export to it again is confusing PowerShell. In any case, it's probably not a good idea to over-write the file in this way as it could lead to corruption. Probably better to write to a separate CSV like this:
function Update-SystemType {
Import-Csv ".\CSV2.csv" | ForEach-Object {$codeHash = #{}}{
$codeHash[$_.Code] = $_
}{}
Import-Csv ".\CSV1.csv" |
ForEach-Object {
$_.LaptopDesktop = $(if($codeHash.ContainsKey($_.Code)){$codeHash[$_.Code].Type}else{"Unknown"})
$_
}
}
Update-SystemType |
Export-Csv '.\CSV3.csv' -Force -NoTypeInformation
If you really want to replace the original afterwards, then you can over-write it like this:
Move-Item -Path .\CSV3.csv -Destination .\CSV1.csv -Force

Answer 2

When posting csv sample data, either use the real comma delimited format -or-
the columnar representation after Import-Csv.
## Q:\TEst\2019\01\17\SO_54236818.ps1
$Mastercsv = Import-Csv ".\CSV1.csv"
$Productinfo = Import-Csv ".\CSV2.csv"
foreach($record in $Mastercsv){
$record.LaptopDesktop = ($Productinfo|Where-Object Code -eq $record.code).Type
}
$Mastercsv | Format-Table -Auto
Sample output
Computer Product Code Country Department LaptopDesktop
-------- ------- ---- ------- ---------- -------------
Com1 EliteDesk 705 HP2190 AU FN D
Com2 EliteBook 830 HP1023 AU IT L
Com3 EliteBook 830 HP1023 FR FN L
Com4 Zbook 15U HP2020 IN FN L
Com5 OptiPlex 3010 DL1721 FR FN D
Com6 unknown na DE IT