function Get-FileEncoding {

<#

[CmdletBinding()]

param(

[Parameter(ValueFromPipeline, ValueFromPipelineByPropertyName, Mandatory,

Position = 0)]

[Alias("FullName")]

$Path

)

PROCESS {

## First, check if the file is binary. That is, if the first

## 5 lines contain any non-printable characters.

$nonPrintable = [char[]] (0..8 + 10..31 + 127 + 129 + 141 + 143 + 144 + 157)

$lines = Get-Content $Path -ErrorAction Ignore -TotalCount 5

$result = @($lines | Where-Object { $_.IndexOfAny($nonPrintable) -ge 0 })

if ($result.Count -gt 0) {

"Binary"

return

}

## Next, check if it matches a well-known encoding.

## The hashtable used to store our mapping of encoding bytes to their

## name. For example, "255-254 = Unicode"

$encodings = @{ }

## Find all of the encodings understood by the .NET Framework. For each,

## determine the bytes at the start of the file (the preamble) that the .NET

## Framework uses to identify that encoding.

foreach ($encoding in [System.Text.Encoding]::GetEncodings()) {

$preamble = $encoding.GetEncoding().GetPreamble()

if ($preamble) {

$encodingBytes = $preamble -join '-'

$encodings[$encodingBytes] = $encoding.GetEncoding()

}

}

## Find out the lengths of all of the preambles.

$encodingLengths = $encodings.Keys | Where-Object { $_ } |

Foreach-Object { ($_ -split "-").Count }

## Assume the encoding is UTF7 by default

$result = [System.Text.Encoding]::UTF7

## Go through each of the possible preamble lengths, read that many

## bytes from the file, and then see if it matches one of the encodings

## we know about.

foreach ($encodingLength in $encodingLengths | Sort -Descending) {

$bytes = Get-Content -Encoding byte -readcount $encodingLength $path | Select -First 1

$encoding = $encodings[$bytes -join '-']

## If we found an encoding that had the same preamble bytes,

## save that output and break.

if ($encoding) {

$result = $encoding

break

}

}

[PSCustomObject][ordered]@{File = $Path; Encoding = $result }

}

}