download web document VB.NET

[seraieis]

Good morning experts!

I'm trying to figure out a way to download a report from one of my companies intranet sites, and I've hit a bit of a snag.

The report differs by two items: the session id (auto-generated on log on), and the report key (which I get from another system). I've used screen scraping to get the session ID at log on, and I provide the key.

However, when I try to use My.Computer.Network.DownloadFile, the file that downloads is a page (within the system) that says the session has expired. I have a feeling it's because there's a web-based application that generates the report.

        path = _
            "http://system.internal.com/xcgi/xnet.exe?sys=sys" & _
            "&ses=" & session & _
            "&ISN=&TRN=&cmd=DWN&rid=" & _
            "&rpt=/EDICLAIM/HOSPMED%2ECCMEDC%2E%4002" & _
            "&ver=1722" & _
            "&ixn=" & s & "&ixv=" & key
 
        Try
            Dim file As String = _
                My.Computer.FileSystem.SpecialDirectories.Desktop _
                & "\test.xls"
            If My.Computer.FileSystem.FileExists(file) Then Kill(file)
            My.Computer.Network.DownloadFile(path, file)
            Process.Start(file)
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
 

Now, if I copy the string into the browser, it opens a file download dialog and I can save it as normal. However, trying to use VB to do the same results in an error. Does anyone have any suggestions as to how to overcome this?

Thank you!

[Plater]

You should be using HttpWebRequest to download the file should you not?

[seraieis]

It's funny you should say that! I continued trying to figure this out, and just tested using that:

            Dim request As HttpWebRequest = WebRequest.Create(path)
            Dim response As HttpWebResponse = request.GetResponse()
            Dim reader As New StreamReader(response.GetResponseStream())
            Dim f As New IO.StreamWriter(file)
 
            f.Write(reader.ReadToEnd())
            f.Close()
            reader.Close()
 
            Process.Start(file)
 

The file that opens after this runs is still the error page. Is there something I'm missing?

[Plater]

You may need to do the entire process for grabbing the session id and etc with HttpWebRequest objects?

If you paste the path you provided into a new IE (or FF) window, does it give the correct response? (I say new window, but I mean new instance, re-using an old instance might send down hidden headers obtained from a previous successfull request to the website)

[seraieis]

I tried copying the address into another window and it gave the error page.

Looking at the JavaScript behind the web page's download button, it looks simple enough:

function goToDownload() {
  if (GetCookie("actind") == "") {
     window.location = "/xcgi/xnet.exe?sys=JHSE2&ses=0ECCE09B851B522572AFFB6451E39C6F55EAFFDC&ISN=&TRN=&cmd=DWN&rid=&rpt=/CLM/HOSPMED%2ECCMEDC%2E%4002&ver=1722&ixn=CKEY$&ixv=2008011840100401017442";
  }
}
 

The string generate by the program:

xcgi/xnet.exe?sys=JHSE2&ses=0ecce09b851b522572affb6451e39c6f55eaffdc&ISN=&TRN=&cmd=DWN&rid=&rpt=/CLM/HOSPMED%2ECCMEDC%2E%4002&ver=1722&ixn=CKEY$&ixv=2008011840100401017442
 

Now, I know nothing about cookies, so I'm not sure that it's referencing. Plus, reading through the cookie itself, I couldn't find anything with a label of "actind", so I'm a little confused.

Is there a way to trick the WebRequest into thinking it's coming from the same instance?

[seraieis]

I had a breakthrough!

        Dim d As System.Windows.Forms.HtmlDocument = Me.WebBrowser1.Document
        d.InvokeScript("goToDownload")
 

That brings up the dialog box for saving something from the internet to your computer. Now, short of simulating keystrokes, is there a way to NOT have the save file dialog box appear?