Functions/Get-UrlContent.ps1
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function Get-UrlContent { <# .SYNOPSIS To get the HTML content of a specified URL .DESCRIPTION To get the HTML content of a specified URL .PARAMETER URL The URL string, which should begin with "https://" or "http://" .PARAMETER IgnoreSslError To ignore any SSL errors that are generated .NOTES This function only exists for PowerShell versions prior to the inclusion of Invoke-WebRequest .EXAMPLE Get-UrlContent -URL "http://www.google.com" Would return: The HTML content that is found on Google's homepage .EXAMPLE Get-UrlContent -URL "https://secureServer" Assuming the computer does not have a valid certificate for secureServer then this would return: $Null .EXAMPLE Get-UrlContent -URL "https://secureServer" -IgnoreSslError Assuming the computer does not have a valid certificate for secureServer and you wish to override the SSL error then this would return: The HTML content that is found on secureServer's homepage .OUTPUTS Either $Null if any errors exist or a [string] if successful #> [CmdletBinding()] [Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseProcessBlockForPipelineCommand', '')] Param ( [parameter(ValueFromPipeLine, HelpMessage = 'Add help message for user', ValueFromPipeLineByPropertyName, Mandatory)] [string] $URL, [parameter()] [switch] $IgnoreSslError ) begin { Write-Verbose -Message "Starting [$($MyInvocation.Mycommand)]" $oldEA = $ErrorActionPreference $ErrorActionPreference = 'continue' Write-Verbose -Message "Saving current value of `$ErrorActionPreference [$($oldEa)] and setting it to 'Stop'" } process { if ($IgnoreSslError) { Write-Verbose -Message 'Turning on IgoreSslError' [System.Net.ServicePointManager]::ServerCertificateValidationCallBack = { $true } } $htmlContent = $null Write-Verbose -Message 'Creating a webclient' $webClient = New-Object -TypeName System.Net.WebClient Write-Verbose -Message "Requesting content from [$($URL)]" try { $htmlContent = $webClient.downloadstring($URL) } catch { Write-Error -Message "Could not connect to [$($URL)]" } finally { if ($IgnoreSslError) { Write-Verbose -Message 'Turning off IgoreSslError' [System.Net.ServicePointManager]::ServerCertificateValidationCallBack = { $false } } } Write-Verbose -Message 'Disposing of webClient connection' $webClient.Dispose() Remove-Variable -Name webClient if ($htmlContent) { Write-Verbose -Message 'Successful download of HTML content' Write-Output -InputObject $htmlContent } else { Write-Verbose -Message 'Unsuccessful download of HTML content' return } } end { Write-Verbose -Message "Resetting value of `$ErrorActionPreference back to [$($oldEa)]" $ErrorActionPreference = $oldEA Write-Verbose -Message "Ending [$($MyInvocation.Mycommand)]" } } |