Error handling and updated help

WifiProfilePassword/Get-WifiProfilePassword.ps1

@@ -10,7 +10,7 @@ Uses netsh to retrieve all wifi profiles and then extract the corrosponding pass
 The name of the network profile to be retrieved, by default all profiles are retrieved
 
 .NOTES
-Name:        New-ZeroFile
+Name:        Get-WifiProfilePassword
 Author:      Jaap Brasser
 DateCreated: 2017-10-01
 DateUpdated: 2017-10-03
@@ -25,14 +25,38 @@ Get-WifiProfilePassword
 
 Description
 -----------
-Retrieves all the passwords and profiles
+Retrieves all the wifi passwords for each saved network on this system
+
+.EXAMPLE
+"Wifi Profile 1","Jaap's wifi" | Get-WifiProfilePassword
+
+Description
+-----------
+Retrieves the wifi passwords for "Wifi Profile 1" and "Jaap's wifi" by using pipelining
+
+.EXAMPLE
+Get-WifiProfilePassword -WifiProfile "Wifi Profile 1","Jaap's wifi"
+
+Description
+-----------
+Retrieves the wifi passwords for "Wifi Profile 1" and "Jaap's wifi"
 #>
 
 
     param(
+        [Parameter(
+            Mandatory         = $false,
+            ValueFromPipeline = $true
+        )]
         [string[]] $WifiProfile
     )
 
+    begin {
+        if (-not (Get-Command -Name netsh.exe -CommandType Application -ErrorAction SilentlyContinue)) {
+            throw 'Netsh not found on this system, script terminated'
+        }
+    }
+
     process {
         if ($WifiProfile) {
             foreach ($CurrentWifi in $WifiProfile) {