public/Convert-JsonToCsv.ps1

function Convert-JsonToCsv {
    <#
    .SYNOPSIS
        Convert a JSON file to CSV format
    .DESCRIPTION
        Convert a JSON file to CSV format file.
    .PARAMETER Path
        Path and name of JSON file.
    .PARAMETER TranslateFileName
        Optional. Export to file using same path and basename but use the new extension.
    .PARAMETER OutputFile
        Path and name of CSV output file. The default is to use the same path and filename replacing the file extension with .csv
    .EXAMPLE
        Convert-JsonToCsv -Path "c:\temp\myfile.json"

        Exports the CSV file "c:\temp\myfile.csv"
    .EXAMPLE
        Get-ChildItem -Path "c:\temp" -Filter "*.json" | Select FullName | Convert-JsonToCsv

        Exports each JSON file in the path "c:\temp" to a new CSV file with the same filename and in the same folder path
    .EXAMPLE
        Convert-JsonToCsv -Path "c:\temp\myfile.json" -OutputFile "f:\docs\newfile.csv"

        Exports the JSON file to a different path and CSV filename.
    .EXAMPLE
        Convert-JsonToCsv -Path "c:\temp\myfile.json" -TranslateFileName

        Exports the JSON file to c:\temp\myfile.csv
    .LINK
        https://github.com/Skatterbrainz/helium/blob/master/docs/Convert-JsonToCsv.md
    #>

    [CmdletBinding()]
    param (
        [parameter(Mandatory=$True,ValueFromPipeline=$True)][string]$Path,
        [parameter()][switch]$TranslateFileName,
        [parameter()][string]$OutputFile = ""
    )
    BEGIN {}
    PROCESS {
        try {
            $jsonfile = Get-Item -Path $Path -ErrorAction Stop
            if (![string]::IsNullOrWhiteSpace($OutputFile)) {
                Get-Content -Path $jsonfile.FullName | ConvertFrom-Json | Export-Csv -Path $OutputFile -NoTypeInformation -Force
                Write-Host "Exported: $OutputFile"
            } elseif ($TranslateFileName) {
                $OutputFile = Join-Path $jsonfile.Directory "$($jsonfile.BaseName).csv"
                Get-Content -Path $jsonfile.FullName | ConvertFrom-Json | Export-Csv -Path $OutputFile -NoTypeInformation -Force
                Write-Host "Exported: $OutputFile"
            } else {
                Get-Content -Path $jsonfile.FullName | ConvertFrom-Json
            }
        } catch {
            Write-Error $_.Exception.Message
        }
    }
    END {}
}