functions/ConvertFrom-Fwsv.ps1
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# <copyright file="ConvertFrom-Fwsv.ps1" company="Endjin Limited"> # Copyright (c) Endjin Limited. All rights reserved. # </copyright> <# .SYNOPSIS Converts a string containing fixed-width, space-separated tabulated values into a PowerShell object. .DESCRIPTION Converts a string containing fixed-width, space-separated tabulated values into a PowerShell object. The column headers are used to determine the width of each column in the tabulated values. .INPUTS The lines of a fixed-width space-separated tabulated values. .PARAMETER InputObject The lines of a fixed-width space-separated tabulated values. .PARAMETER Headers The column headers of tabulated values - used to determine width of each column in the tabulated values. #> function ConvertFrom-Fwsv { [CmdletBinding()] param ( [Parameter(Mandatory = $true, ValueFromPipeline = $true)] [AllowEmptyString()] # allow empty lines to be processed [string[]]$InputObject, [Parameter(Mandatory = $true)] [string[]]$Headers ) begin { $columnOffsets = @() $result = @() } process { # When processing via the pipeline, this block will be called for each row # so we need to ensure we only calculate the column offsets once if ($columnOffsets.Count -eq 0) { # Calculate the column offset for each header using the first row $headerRow = $InputObject[0] foreach ($header in $Headers) { $offset = $headerRow.IndexOf($header) if ($offset -eq -1) { throw "Header '$header' not found in input data: '$headerRow'" } $columnOffsets += $offset } # If we are processing via the pipeline then skip the rest of the process block # as we don't want to create a row for the column headers if ($MyInvocation.ExpectingInput) { return } } # Use those offsets to extract the values for each row foreach ($row in $InputObject[1..($InputObject.Count-1)]) { # Skip empty rows if ($row.Length -eq 0) { continue } $rowObject = [ordered]@{} # Process each column foreach ($columnNum in 0..($columnOffsets.Count-1)) { $currentColumnOffset = $columnOffsets[$columnNum] if ($currentColumnOffset -ge $row.Length) { # We have a truncated row (i.e. the last column is missing) $rowObject[$Headers[$columnNum]] = '' } else { # Calculate the offset for where the next column starts so we can extract the value of the current column $isLastColumn = $columnNum+1 -ge $columnOffsets.Count if ($isLastColumn) { # If this is the last column, then the 'next column' starts at the end of the row $currentColumnWidth = $row.Length - $currentColumnOffset } else { # Otherwise, it starts at the next column offset or the end of the row if it is truncated (i.e. the last column is missing) $nextColumnOffset = [int]::Min($row.Length, $columnOffsets[$columnNum+1]) $currentColumnWidth = $nextColumnOffset - $currentColumnOffset } $rowObject[$Headers[$columnNum]] = $row.SubString($currentColumnOffset, $currentColumnWidth).TrimEnd() } } $result += [pscustomobject]$rowObject } } end { $result } } |