Powershell cruise control build output parser

<#
.Synopsis
   Write-XmlPathOutput processes all files in a directory for a given XPath expression and puts the results to .txt files of the same name
.EXAMPLE
   Write-XmlPathOutput -DirectoryPath DirectoryPath -XPath //*/project
.INPUTS
   DirectoryPath - the path to the directory
   XPath - the xpath you wish to use
.OUTPUTS
   .txt text files in the same directory
#>
function Write-XmlPathOutput
{
    [CmdletBinding(DefaultParameterSetName='Parameter Set 1',
                  SupportsShouldProcess=$false,
                  PositionalBinding=$false,
                  HelpUri = 'http://merrickchaffer.blogspot.com/',
                  ConfirmImpact='Medium')]
    [OutputType([String])]
    Param
    (
        # Param1 help description
        [Parameter(Mandatory=$true,
                   ValueFromPipeline=$true,
                   ValueFromPipelineByPropertyName=$true,
                   ValueFromRemainingArguments=$false,
                   Position=0,
                   ParameterSetName='Parameter Set 1')]
        [ValidateNotNull()]
        [Alias("p")]
        [String]
        $DirectoryPath = (Get-Location).Path,

        # xpath help description
        [Parameter(Mandatory=$false, ParameterSetName='Parameter Set 1', Position=1,
                    ValueFromPipeline=$true,
                   ValueFromPipelineByPropertyName=$true,
                   ValueFromRemainingArguments=$false )]
        [Alias("x")]
        [String]
        $XPath = "//*/project/@file"

    )

    Begin
    {
    }
    Process
    {
        if ($pscmdlet.ShouldProcess("Target", "Operation"))
        {
            $files = Get-ChildItem (Get-ChildItem $DirectoryPath\*.xml)
            if ($files -ne $null -and $files.Length -gt 0) {
               
                ForEach ($file in $files) {
                 
                  $OutFile = [string]::Concat($file.FullName, ".txt")
                 
                  Select-Xml -Path $file.FullName -XPath $XPath | Select -ExpandProperty Node | Out-File $OutFile

                }
            }

        }
    }
    End
    {
    }
}

Write-XmlPathOutput -DirectoryPath C:\temp -XPath "//*/project/@file"