Samples zum RSS MSDN Webcast von Hannes Preishuber 28.03.2006

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Q&D RSS in Website einbauen

RSS mit ETAG erzeugen

<%@ Page Language="VB" ContentType="text/xml" EnableViewState="false" %>

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim fakeetag As String = "xxx01"
        Dim etag As String = Request.Headers.Get("If-None-Match")
        Response.Cache.SetCacheability(HttpCacheability.Public)
        Response.Cache.SetETag(fakeetag)
        If fakeetag = etag Then
            Response.StatusCode = 304
            Response.Flush()
            Response.End()
            Repeater1.Visible = False
            
        End If
    End Sub
</script>
        <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>"
            SelectCommand="SELECT [OrderID], [CustomerID], [RequiredDate], [ShipName] FROM [Orders]">
        </asp:SqlDataSource>
        <asp:Repeater ID="Repeater1" runat="server" DataSourceID="SqlDataSource1">
        <HeaderTemplate>
        <rss version="2.0">
        <channel>
        <title>ppedv Bestellungen</title>
        <link>http://www.ppedv.de</link>
        <image><url>http://www.ppedv.de/ppedvk.gif</url></image>
        </HeaderTemplate>
        <FooterTemplate>
        </channel>
        </rss>
        </FooterTemplate>
        <ItemTemplate>
        <item>
        <title><%#librss.FormatForXML(Eval("shipname"))%></title>
        <link>http://www.ppedv.de/orders.aspx?id=<%#librss.FormatForXML(Eval("orderid"))%></link>
        <author><%#librss.FormatForXML(Eval("customerid"))%></author>
        <pubDate><%#librss.FormatForXML(Eval("requireddate", "{0:r}"))%></pubDate>
        </item>
        </ItemTemplate>

</asp:Repeater>

Winforms VB 2005 RSS Reader nach allen regeln der Kunst (GZIP, ETAG)

Imports System.net
Imports System.io
Imports System.Xml
Public Class Display
    Private ds As DataSet
    Private etag As String
    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Dim reqRSS As HttpWebRequest = WebRequest.Create(txtRSSUrl.Text)
        reqRSS.Accept = "*/*"
        reqRSS.UserAgent = "Mozilla/4.0 (ppedv RSS Reader;)"
        reqRSS.Headers.Set(HttpRequestHeader.AcceptEncoding, "gzip, deflate")
        reqRSS.Headers.Set(HttpRequestHeader.IfNoneMatch, etag)
        Try
            Dim resRSS As HttpWebResponse = CType(reqRSS.GetResponse(), HttpWebResponse)
            Dim streamRSS As Stream = resRSS.GetResponseStream()
            If String.Compare(resRSS.ContentEncoding, "gzip", True) = 0 Then
                Dim gzipRSS As New Compression.GZipStream(streamRSS, Compression.CompressionMode.Decompress)
                ds.ReadXml(gzipRSS)
                gzipRSS.Close()
            Else
                Dim RSS As New StreamReader(streamRSS)
                ds.ReadXml(RSS)
                RSS.Close()
            End If
            streamRSS.Close()
            etag = resRSS.Headers.Get("ETag")
            resRSS.Close()
            ToolStripStatusLabel1.Text = Date.Now.ToLongTimeString + ": 200  "
        Catch ex As WebException
            If CType(ex.Response, HttpWebResponse).StatusCode = HttpStatusCode.NotModified Then
                ToolStripStatusLabel1.Text = Date.Now.ToLongTimeString + ": 304"
            End If
        End Try
        DataGridView1.DataSource = ds.Tables("item").DefaultView
    End Sub

Private Sub txtIntervall_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtIntervall.TextChanged
        Timer1.Interval = CInt(txtIntervall.Text) * 1000
        If Len(txtRSSUrl.Text) > 1 Then
            Timer1.Enabled = True
        End If
    End Sub

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        ds = New DataSet
    End Sub
End Class