Sometime ago I wrote an article about Exporting Datagrid to Excel, Word and Text Files. Sometimes we need to export Dataset to xml file. This is pretty simple as all you need is a literal control which will render the data to the output stream. Check out the code below:

  SqlConnection myConnection = new SqlConnection(ConnectionString);
        SqlDataAdapter ad = new SqlDataAdapter("SELECT * FROM Categories", myConnection);
        DataSet ds = new DataSet();
        ad.Fill(ds, "Categories");

        Literal l = new Literal();
        l.Text = ds.GetXml(); 

        // Preparing to xml the file
        Response.Clear();

        Response.AddHeader("content-disposition", "attachment;filename=FileName.xml");

        Response.Charset = "";

        Response.Cache.SetCacheability(HttpCacheability.NoCache);

        Response.ContentType = "application/vnd.xml";

        System.IO.StringWriter stringWrite = new System.IO.StringWriter();

        System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);

        l.RenderControl(htmlWrite);       
    

        Response.Write(stringWrite.ToString());

        Response.End();

This will prompt a message asking that if you want to save the file or open it directly from its current location.

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