import xlsx converted to csv to powershell - excel

Question

I need to import csv file to my PS script. In the same script I have a function to convert an xlsx file to csv, which I need to import. But I can't find a way to do that. I tried three approaches:
$CSVLicence = Import-Csv (ConvertXLSX -File $Licence) -Delimiter "," -Encoding UTF8
Where ConvertXLSX is the function to convert xlsx to csv, $Licence is a variable defined at the beginning of the script. The second approach is this:
$CSVfile = ConvertXLSX -File $Licence
$CSVLicence = ImportCsv $CSVfile -Delimiter "," -Encoding UTF8
In both cases I get an error message on the column right after "Import-Csv", that argument Path is null or empty.
The third approach was defining the path literally, which is not really a good solution, but should work, if executor of the file runs it in correct folder and uses correct file name. In this case I get an error "The member "Proemail Exchg Business" is already present" in front of the "Import-Csv" cmdlet
The csv file gets created and it looks precisely as it should, so there's obviously not an error in the converting function.
The ConvertXLSX function is defined like this:
$Licence = "licence"
Function ConvertXLSX ($File)
{
$PWD = "r:\Licence\"
$ExcelFile = $PWD + $File + ".xlsx"
$Excel = New-Object -ComObject Excel.Application
$Excel.Visible = $false
$Excel.DisplayAlerts = $false
$wb = $Excel.Workbooks.Open($ExcelFile)
foreach ($ws in $wb.Worksheets | where {$_.name -eq "Pridani"})
{
$ws.SaveAs($PWD + $File + ".csv",6)
}
$Excel.Quit()
}
ConvertXLSX -File $Licence
The function creates the csv file successfully, without any problems

Answer 1

You're currently using the wrong cmdlet. Import-Csv is designed to be used with a file.csv, not a string object or otherwise. There is a cmdlet that exists for that purpose, ConvertFrom-Csv, that takes an -InputObject parameter (indicating it takes pipeline input).
PS C:\> Get-Help -Name 'ConvertFrom-Csv'
SYNTAX
ConvertFrom-Csv [-InputObject] <PSObject[]> [[-Delimiter] <Char>] [-Header <String[]>]
Used in your example:
## Declaration of the delimiter is unnecessary when it's a comma
$CSVLicense = ConvertXLSX -File $Licence | ConvertFrom-Csv

Answer 2

TheIncorrigible1 explained the issue quite well. Now that you've edited the question to add the ConvertXLSX function, we can build on that to get a solution that fits.
$ws.SaveAs($PWD + $File + ".csv",6)
This part is the save to the filename $PWD + $File + ".csv". The number 6 represents the CSV XlFileFormat Enumeration.
The function does not return anything, just performs an action on external file. That's why you are getting the null or empty error. We can get it to return the file path, or to return the data in an object and use ConvertFrom-Csv.
Given your code, the object would require more work as you already have the file path there.
To return file path, change:
}
$Excel.Quit()
}
To:
}
$Excel.Quit()
return $($PWD + $File + ".csv")
}
You code should then work.
You could improve it's readability and conciseness more:
Assign the CSV filename to a variable.
Avoid assigning to $PWD as it's an alias for Get-Location
Get rid of the foreach. You are only getting one sheet and saving that sheet at the moment. If you are doing for multiple sheets, you will have to thing how to pass the multiple paths/object to Import-Csv/ConvertFrom-Csv
Putting it all together:
$Licence = "licence"
Function ConvertXLSX ($File)
{
$rootDir = "r:\Licence\"
$ExcelFile = $rootDir + $File + ".xlsx"
$CSVFile = $ExcelFile.Replace(".xlsx",".csv")
$Excel = New-Object -ComObject Excel.Application
$Excel.Visible = $false
$Excel.DisplayAlerts = $false
$wb = $Excel.Workbooks.Open($ExcelFile)
$ws = $wb.Worksheets | where {$_.name -eq "Pridani"})
$ws.SaveAs($CSVFile,6)
$Excel.Quit()
return CSVFile
}
ConvertXLSX -File $Licence
I get an error "The member "Proemail Exchg Business" is already present" in front of the "Import-Csv" cmdlet
This one is handled in this StackOverflow post. Short version is you have two columns with "Proemail Exchg Business" in the first row.
PowerShell creates an object from the CSV: the column headers must be unique. Either fix in the excel sheet, or manually specify unique headers using -Header as in linked post.