powershell binary file comparison

With PowerShell 4 you can use native commandlets to do this:

function CompareFiles {
    param(
    [string]$Filepath1,
    [string]$Filepath2
    )
    if ((Get-FileHash $Filepath1).Hash -eq (Get-FileHash $Filepath2).Hash) {
        Write-Host 'Files Match' -ForegroundColor Green
    } else {
        Write-Host 'Files do not match' -ForegroundColor Red
    }
}

PS C:> CompareFiles .\20131104.csv .\20131104-copy.csv

Files Match

PS C:> CompareFiles .\20131104.csv .\20131107.csv

Files do not match

You could easily modify the above function to return a $true or $false value if you want to use this programmatically on a large scale

---

EDIT

After seeing this answer, I just wanted to supply larger scale version that simply returns true or false:

function CompareFiles 
{
    param
    (
        [parameter(
            Mandatory = $true,
            HelpMessage = "Specifies the 1st file to compare. Make sure it's an absolute path with the file name and its extension."
        )]
        [string]
        $file1,

        [parameter(
            Mandatory = $true,
            HelpMessage = "Specifies the 2nd file to compare. Make sure it's an absolute path with the file name and its extension."
        )]
        [string]
        $file2
    )

    ( Get-FileHash $file1 ).Hash -eq ( Get-FileHash $file2 ).Hash
}

You could use fc.exe. It comes with Windows. Here's how you would use it:

fc.exe /b d:\local\prodexport2 d:\local\prodexport1 > $null
if (!$?) {
    "The files are different"
}

Another method is to compare the MD5 hashes of the files:

$Filepath1 = 'c:\testfiles\testfile.txt'
$Filepath2 = 'c:\testfiles\testfile1.txt'

$hashes = 
foreach ($Filepath in $Filepath1,$Filepath2)
{
 $MD5 = [Security.Cryptography.HashAlgorithm]::Create( "MD5" )
 $stream = ([IO.StreamReader]"$Filepath").BaseStream
 -join ($MD5.ComputeHash($stream) | 
 ForEach { "{0:x2}" -f $_ })
 $stream.Close()
 }

if ($hashes[0] -eq $hashes[1])
  {'Files Match'}