How to preserve spaces after a CSV import using a powershell script?

Here is a solution that should be more robust (and propably faster) than replacing characters from the CSV file.

It uses the .NET TextFieldParser class from Microsoft.VisualBasic assembly. It has a TrimWhiteSpace attribute which, when set to $false, preserves any leading and trailing whitespace of each field, even if the field is not enclosed in double quotation marks.

I've encapsulated the .NET code in a function named Import-CustomCsv. It supports some additional options of TextFieldParser through various parameters.

Function Import-CustomCsv {
   [CmdletBinding()]
   param (
      [Parameter(Mandatory, ValueFromPipeline)] [String] $Path,
      [String[]] $Delimiter = ',',
      [String[]] $CommentTokens = '#',
      [switch] $TrimWhiteSpace,
      [switch] $HasFieldsEnclosedInQuotes
   )

   # Load Visual Basic assembly if necessary. Seems to be required only for PS 5.
   if (-not ([System.Management.Automation.PSTypeName]'Microsoft.VisualBasic.FileIO.TextFieldParser').Type) {
      Add-Type -AssemblyName 'Microsoft.VisualBasic, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   }   

   # Create a CSV parser
   $csvParser = New-Object Microsoft.VisualBasic.FileIO.TextFieldParser $Path

   try {
      # Set CSV parser options
      $csvParser.SetDelimiters( $Delimiter )
      $csvParser.CommentTokens = $CommentTokens
      $csvParser.TrimWhiteSpace = $TrimWhiteSpace
      $csvParser.HasFieldsEnclosedInQuotes = $HasFieldsEnclosedInQuotes

      # Read the header
      $header = $csvParser.ReadFields()

      while( -not $csvParser.EndOfData ) {
         # Read current line fields, pointer moves to the next line.
         $fields = $csvParser.ReadFields()

         # Associate each field with its name from the header by storing it in an
         # ordered hashtable.
         $namedFields = [ordered]@{}
         for( $i = 0; $i -lt $header.Count; $i++ ) {
            $namedFields[ $header[ $i ] ] = $fields[ $i ]
         }

         # Finally convert fields to PSCustomObject and output (implicitly)
         [PSCustomObject] $namedFields
      }
   }
   finally {
      # Make sure to close the file even in case of an exception.
      $csvParser.Close()
   }
}

Usage example: Parse CSV, preserving whitespace:

Import-CustomCsv test.csv -Delimiter ';'

Output:

ResourceId GermanTranslation   EnglishTranslation Check
---------- -----------------   ------------------ -----
0          Deutscher Text      English text       OK
1            mit Leerzeichen     with spaces      OK

Usage example: Parse CSV, trimming whitespace (like Import-Csv):

Import-CustomCsv test.csv -Delimiter ';' -TrimWhiteSpace

Output:

ResourceId GermanTranslation EnglishTranslation Check
---------- ----------------- ------------------ -----
0          Deutscher Text    English text       OK   
1          mit Leerzeichen   with spaces        OK   

Note:

The above two samples keep field-enclosing double-quotation marks (if any) in the output. To remove double-quotation marks around fields, pass parameter -HasFieldsEnclosedInQuotes.