PowerShell v2 Function Add WebConfigAppSetting

Back in March I posted about a means to write down to web.config files

PowerShell (v2) - Adding AppSettings Elements to Web.config

After revisiting my post I realized it was pretty much wrong and completely useless.  So, I set about to rewrite it with the help of a few folks on the forums.

How can I discard output of pipeline without using Out-Null?

In the end I came up with this:

functionAdd-WebConfigAppSetting

{

     [CmdletBinding()]

     param(

           [Parameter(

                Mandatory = $true

           )]

           [String]

           [ValidateNotNullOrEmpty()]

           $Key,

          

           [Parameter(

                Mandatory = $true

           )]

           [String]

           [ValidateNotNullOrEmpty()]

           $Value,

           [Parameter(

                Mandatory = $true

           )]

           [String]

           [ValidateNotNullOrEmpty()]

           $WebConfigPath

     )

     # Configure function variables

     $timestamp = (Get-Date -Format yyyyMMddHHmmss)

     # Clear variables to prevent reuse

     $appSettings = $node = $xml = $null

     # Output status to host

     Write-Output "Loading file contents."

     # Load content of web.config

     $xml = [xml](get-content($webconfigpath))

     # Backup web.config

     if(-not(Test-Path "$webconfigpath.$timestamp"))

     {

           # Output status to host

           Write-Output "Creating backup."

          

           # Save file

           $xml.Save("$webconfigpath.$timestamp")

     }

     # If appSettings element does not exist

     if($xml.SelectSingleNode(//configuration/appSettings) -eq $null)

     {

           # Output status to host

           Write-Output The appSettings node does not exist. Adding it now.

          

           # if child nodes do not exist create it

           $appSettings = $xml.CreateElement("appSettings")

          

           # Output status to host

           Write-Output "The appSetting ($($key)/$($value)) does not exist. Adding it now."

          

           # add new element called add to //configuration/appSettings

           $node = $xml.CreateNode(element,add,)

          

           # Set attributes for new appSetting

           $node.SetAttribute(key,$key)

           $node.SetAttribute(value,$value)

           # Add $node to //configruation/appsetting element

           [Void] $appSettings.AppendChild($node)

          

           # Add $appSetting node to //configuration element

           [Void] $xml.configuration.AppendChild($appSettings)

           # Output status to host

           Write-Output "Saving changes." 

          

           # Save changes to file

           $xml.Save($webconfigpath)

     }

     else

     {

           # Output status to host

           Write-Output "The //configuration/appSettings element exists. Checking for children nodes."

          

           # Gather //configuration/appSettings data

           $appSettings = $xml.configuration[appSettings]

          

           # Test to see if element has child nodes

           if($appSettings.HasChildNodes)

           {

                # Output status to host

                Write-Output "The appSettings elements has children. Checking arguments against existing values."

          

                # Test to see if key exists.        

                if($appSetting = ($appSettings.ChildNodes | Where {$_.key -eq $key}))

                {

                     # Output status to host

                     Write-Output "The element ($($key)) exists. Comparing values."

               

                     # Test to see if value matches

                     if($appSetting.value -eq $value)

                     {

                           # Value matches. Output status to host.

                           Write-Output "The key/value arguments are already set correctly."

                     }

                     else

                     {

                           # Value does not match. Attempt to update and output status to host.

                     &

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