Passing an array of URLs as an argument to Powershell - parameter-passing

Question

I am trying to write a script that will take a text file containing URL links to documents and download them. I am having a hard time understanding how to pass the arguments and manipulate them in powershell. Here is what I got so far. I think I should be using the param method of taking an argument so I can require it for the script, but $args seemed easier on face value... A little help would be much appreciated.
**UPDATE
$script = ($MyInvocation.MyCommand.Name)
$scriptName = ($MyInvocation.MyCommand.Name -replace "(.ps1)" , "")
$scriptPath = ($MyInvocation.MyCommand.Definition)
$scriptDirectory = ($scriptPath.Replace("$script" , ""))
## ##################################
## begin code for directory creation.
## ##################################
## creates a direcory based on the name of the script.
do {
$scriptFolderTestPath = Test-Path $scriptDirectory\$scriptName -PathType container
$scriptDocumentFolderTestPath = Test-Path $scriptFolder\$scriptName"_Script_Documents" -PathType container
$scriptLogFolderTestPath = Test-Path $scriptFolder\$scriptName"_Script_Logs" -PathType container
if ($scriptFolderTestPath -match "False") {
$scriptFolder = New-Item $scriptDirectory\$scriptName -ItemType directory
}
elseif ($scriptDocumentFolderTestPath -match "False") {
New-Item $scriptFolder\$scriptName"_Script_Documents" -ItemType directory
}
elseif ($scriptLogFolderTestPath -match "False") {
New-Item $scriptFolder\$scriptName"_Script_Logs" -ItemType directory
}
} Until (($scriptFolderTestPath -match "True") -and ($scriptDocumentFolderTestPath -match "True") -and ($scriptLogFolderTestPath -match "True"))
## variables for downloading and renaming code.
$date = (Get-Date -Format yyyy-MM-dd)
## ################################
## begin code for link downloading.
## ################################
## gets contents of the arguement variable.
Get-Content $linkList
## downloads the linked file.
Invoke-WebRequest $linkList
Resulting Errors
PS C:\Windows\system32> C:\Users\Steve\Desktop\Website_Download.ps1
cmdlet Website_Download.ps1 at command pipeline position 1
Supply values for the following parameters:
linkList: C:\Users\Steve\Desktop\linkList.txt
Directory: C:\Users\Steve\Desktop\Website_Download
Mode LastWriteTime Length Name
---- ------------- ------ ----
d---- 10/27/2012 3:59 PM Website_Download_Script_Documents
d---- 10/27/2012 3:59 PM Website_Download_Script_Logs
Get-Content : Cannot find path 'C:\Users\Steve\Desktop\linkList.txt' because it does not exist.
At C:\Users\Steve\Desktop\Website_Download.ps1:42 char:1
+ Get-Content $linkList
+ ~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (C:\Users\Steve\Desktop\linkList.txt:String) [Get-Content], ItemNotFoundException
+ FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.GetContentCommand
Invoke-WebRequest : Could not find file 'C:\Users\Steve\Desktop\linkList.txt'.
At C:\Users\Steve\Desktop\Website_Download.ps1:45 char:1
+ Invoke-WebRequest $linkList
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidOperation: (System.Net.FileWebRequest:FileWebRequest) [Invoke-WebRequest], WebException
+ FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeWebRequestCommand

Answer 1

There is no difference in passing an array of arguments in Powershell, compared to any other type of arguments. See here for how it's done. Considering you have a text file, you don't need to pass an array of arguments, and only need to pass a file name, so just a string.
I don't have any experience with Powershell 3.0, which is what you are using (judging by the presence of Invoke-WebRequest in your code), but I would start with something like this:
$URLFile = #"
http://www.google.ca
http://www.google.com
http://www.google.co.uk/
"#
$URLs = $URLFile -split "`n";
$savedPages = #();
foreach ($url in $URLs) {
$savedPages += Invoke-WebRequest $url
}
That is, you have a single file, all in one place, and make sure you receive your content correctly. Not sure why you would need Start-BitsTransfer, since Invoke-WebRequest will already get you page contents. Note that I did not do anything with $savedPages, so my code is effectively useless.
After that, contents of $URLFile goes into a file and you replace a call to it with
gc "Path_To_Your_File"`
If still working, introduce a $Path parameter to your script like this:
param([string]$Path)
test again, and so on. If you are new to Powershell, always start with smaller code pieces and keep growing to include all functionality you need. If you start with a big piece, chances are you will never finish.

Answer 2

Figured this out with the link from Neolisk about handling params. Then changed some code at the end to create another variable and handle things as I normally would. Just some confusion with passing params.
## parameter passed to the script.
param (
[parameter(Position=0 , Mandatory=$true)]
[string]$linkList
)
## variables for dynamic naming.
$script = ($MyInvocation.MyCommand.Name)
$scriptName = ($MyInvocation.MyCommand.Name -replace "(.ps1)" , "")
$scriptPath = ($MyInvocation.MyCommand.Definition)
$scriptDirectory = ($scriptPath.Replace("$script" , ""))
## ##################################
## begin code for directory creation.
## ##################################
## creates a direcory based on the name of the script.
do {
$scriptFolderTestPath = Test-Path $scriptDirectory\$scriptName -PathType container
$scriptDocumentFolderTestPath = Test-Path $scriptFolder\$scriptName"_Script_Documents" -PathType container
$scriptLogFolderTestPath = Test-Path $scriptFolder\$scriptName"_Script_Logs" -PathType container
if ($scriptFolderTestPath -match "False") {
$scriptFolder = New-Item $scriptDirectory\$scriptName -ItemType directory
}
elseif ($scriptDocumentFolderTestPath -match "False") {
New-Item $scriptFolder\$scriptName"_Script_Documents" -ItemType directory
}
elseif ($scriptLogFolderTestPath -match "False") {
New-Item $scriptFolder\$scriptName"_Script_Logs" -ItemType directory
}
} Until (($scriptFolderTestPath -match "True") -and ($scriptDocumentFolderTestPath -match "True") -and ($scriptLogFolderTestPath -match "True"))
## variables for downloading and renaming code.
$date = (Get-Date -Format yyyy-MM-dd)
## ################################
## begin code for link downloading.
## ################################
## gets contents of the arguement variable.
$webTargets = Get-Content $linkList
## downloads the linked file.
Invoke-WebRequest $webTargets