ConvertCSV-ToExcel.ps1

Function Release-Ref ($ref) 
    {
        ([System.Runtime.InteropServices.Marshal]::ReleaseComObject(
        [System.__ComObject]$ref) -gt 0)
        [System.GC]::Collect()
        [System.GC]::WaitForPendingFinalizers() 
    }

Function ConvertCSV-ToExcel
{
<#   
  .SYNOPSIS  
    Converts one or more CSV files into an excel file.
     
  .DESCRIPTION  
    Converts one or more CSV files into an excel file. Each CSV file is imported into its own worksheet with the name of the
    file being the name of the worksheet.
       
  .PARAMETER inputfile
    Name of the CSV file being converted
  
  .PARAMETER output
    Name of the converted excel file
       
  .EXAMPLE  
  Get-ChildItem *.csv | ConvertCSV-ToExcel -output 'report.xlsx'
  
  .EXAMPLE  
  ConvertCSV-ToExcel -inputfile 'file.csv' -output 'report.xlsx'
    
  .EXAMPLE      
  ConvertCSV-ToExcel -inputfile @("test1.csv","test2.csv") -output 'report.xlsx'
  
  .NOTES
  Author: Boe Prox									      
  Date Created: 01SEPT210								      
  Last Modified:  
     
#>
     
#Requires -version 2.0  
[CmdletBinding(
    SupportsShouldProcess = $True,
    ConfirmImpact = 'low',
	DefaultParameterSetName = 'file'
    )]
Param (    
    [Parameter(
     ValueFromPipeline=$True,
     Position=0,
     Mandatory=$True,
     HelpMessage="Name of CSV/s to import")]
     [ValidateNotNullOrEmpty()]
    [array]$inputfile,
    [Parameter(
     ValueFromPipeline=$False,
     Position=1,
     Mandatory=$True,
     HelpMessage="Name of excel file output")]
     [ValidateNotNullOrEmpty()]
    [string]$output    
    )

Begin {     
    #Configure regular expression to match full path of each file
    [regex]$regex = "^\w\:\\"
    
    #Find the number of CSVs being imported
    $count = ($inputfile.count -1)
   
    #Create Excel Com Object
    $excel = new-object -com excel.application
    
    #Disable alerts
    $excel.DisplayAlerts = $False

    #Show Excel application
    $excel.Visible = $False

    #Add workbook
    $workbook = $excel.workbooks.Add()

    #Remove other worksheets
    $workbook.worksheets.Item(2).delete()
    #After the first worksheet is removed,the next one takes its place
    $workbook.worksheets.Item(2).delete()   

    #Define initial worksheet number
    $i = 1
    }

Process {
    ForEach ($input in $inputfile) {
        #If more than one file, create another worksheet for each file
        If ($i -gt 1) {
            $workbook.worksheets.Add() | Out-Null
            }
        #Use the first worksheet in the workbook (also the newest created worksheet is always 1)
        $worksheet = $workbook.worksheets.Item(1)
        #Add name of CSV as worksheet name
        $worksheet.name = "$((GCI $input).basename)"

        #Open the CSV file in Excel, must be converted into complete path if no already done
        If ($regex.ismatch($input)) {
            $tempcsv = $excel.Workbooks.Open($input) 
            }
        ElseIf ($regex.ismatch("$($input.fullname)")) {
            $tempcsv = $excel.Workbooks.Open("$($input.fullname)") 
            }    
        Else {    
            $tempcsv = $excel.Workbooks.Open("$($pwd)\$input")      
            }
        $tempsheet = $tempcsv.Worksheets.Item(1)
        #Copy contents of the CSV file
        $tempSheet.UsedRange.Copy() | Out-Null
        #Paste contents of CSV into existing workbook
        $worksheet.Paste()

        #Close temp workbook
        $tempcsv.close()

        #Select all used cells
        $range = $worksheet.UsedRange

        #Autofit the columns
        $range.EntireColumn.Autofit() | out-null
        $i++
        } 
    }        

End {
    #Save spreadsheet
    $workbook.saveas("$pwd\$output")

    Write-Host -Fore Green "File saved to $pwd\$output"

    #Close Excel
    $excel.quit()  

    #Release processes for Excel
    $a = Release-Ref($range)
    }
}