Get-FileHash

Get-FileHash.ps1

function Get-FileHash
{
	param( [string]$filePath,
           [string]$alg = 'SHA256')

    $stream = $null
    $filePath = Resolve-Path $filePath

    try
    {
        $algorithm = [Security.Cryptography.HashAlgorithm]::Create($alg)
        $stream = ([IO.StreamReader]$filePath).BaseStream
        -join ($algorithm.ComputeHash($stream) | ForEach { "{0:x2}" -f $_ })
    }
    catch [Exception]{
        Write-Error $_
    }
    finally
    {
        if($stream -ne $null)
        {
            $stream.Close()
        }
    }
}