function Update-SourceVersion
{
    Param ([string]$Version)
    $NewVersion = ‘AssemblyVersion("‘ + $Version + ‘.*")’;
    foreach ($o in $input)
    {
        Write-output $o.FullName
        $TmpFile = $o.FullName + “.tmp”
        get-content $o.FullName |
        %{$_ -replace ‘AssemblyVersion\("(\d+\.\d+\.\d+)\.\*"\)’, $NewVersion  }  > $TmpFile
        move-item $TmpFile $o.FullName -force
    }
}

function Update-AllAssemblyInfoFiles ( $version )
{
    foreach ($file in “AssemblyInfo.cs”, “AssemblyInfo.vb” )
    {
        get-childitem -recurse |? {$_.Name -eq $file} | Update-SourceVersion $version ;
    }
}

# validate arguments
$r= [System.Text.RegularExpressions.Regex]::Match($args[0], "^\d+\.\d+\.\d+$");
if ($r.Success)
{
    Update-AllAssemblyInfoFiles $args[0];
}
else
{
    echo ” “;
    echo “Error: Input version does not match x.y.z format!”
    echo ” “;
    echo "Unable to apply version to AssemblyInfo.cs files";
}