Trying to retrieve webpage after logging in

[ckoniecny]

I'm trying to log into a page, and retrieve the HTML, which can only be retrieved once I log in. If I used the URL

 http://www.mywebsite.com/login.php?username=myusername&password=mypassword

explicitly in the web browser, it works fine and I log in, but when I try to do it in the VB .NET code, it doesn't work. I provided the code below.

    Private Sub btnSync_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSync.Click
        Dim request As WebRequest = WebRequest.Create("http://www.mywebsite.com/login.php?username=myusername&password=mypassword")
        Dim response As WebResponse = request.GetResponse()
        Dim s As Stream = response.GetResponseStream()
        Dim sr As StreamReader = New StreamReader(s, Encoding.ASCII)
        Dim doc As String = sr.ReadToEnd()

        Debug.Print(doc)
    End Sub

Any ideas why this isnt working?