function InvokeWebRequest ([string]$url)
{
    try
    {
        $webrequest = [System.Net.WebRequest]::Create($url)
        $response = $webrequest.GetResponse()
        $stream = $response.GetResponseStream()
        $sr = new-object System.IO.StreamReader($stream)
        $content = $sr.ReadToEnd();
        return $content
    }
    catch { Write-Error $_.Exception.Message }
    finally
    {
        if($sr -ne $null) { $sr.Close(); }
        if($response -ne $null) { $response.Close(); }
    }
}