gistfile1.ps1

##Usage

$a = Convert-JsonToXml "{foo: 1, bar: 2}"

write-host $a.root.foo
write-host $a.root.bar

###

###################### JSON PARSING
Add-Type -Assembly System.ServiceModel.Web,System.Runtime.Serialization
$utf8 = [System.Text.Encoding]::UTF8

function Write-Stream {
	PARAM(
	   [Parameter(Position=0)]$stream,
	   [Parameter(ValueFromPipeline=$true)]$string
	)
	PROCESS {
	  $bytes = $utf8.GetBytes($string)
	  $stream.Write( $bytes, 0, $bytes.Length )
	}  
}

function Convert-JsonToXml {
	PARAM([Parameter(ValueFromPipeline=$true)][string[]]$json)
	BEGIN {
	   $mStream = New-Object System.IO.MemoryStream
	}
	PROCESS {
	   $json | Write-Stream -Stream $mStream
	}
	END {
	   $mStream.Position = 0
	   try
	   {
		  $jsonReader = [System.Runtime.Serialization.Json.JsonReaderWriterFactory]::CreateJsonReader($mStream,[System.Xml.XmlDictionaryReaderQuotas]::Max)
		  $xml = New-Object Xml.XmlDocument
		  $xml.Load($jsonReader)
		  $xml
	   }
	   finally
	   {
		  $jsonReader.Close()
		  $mStream.Dispose()
	   }
	}
}
###################### END OF PARSING