FileUploadAspNet.cs

        ///<summary>Upload a file using the Asp.Net 2.0 Upload control.
        ///Requires a button to which this handler responds to Onclick.
        ///</summary>
        protected void UploadBtn_Click(object sender, EventArgs e) {
            try {
                if (FileUpload1.HasFile) {
                    bool failure = false;

                    if (!FileUpload1.FileName.ToLowerInvariant().EndsWith(".xml")) {
                        failure = true;
                    }
                    StreamReader reader = new StreamReader(FileUpload1.FileContent);
                    string xmlContent = reader.ReadToEnd();
                    if (!xmlContent.TrimStart().StartsWith("<?xml")) {
                        failure = true;
                    }

                    if (!failure) {
                        Label1.Text = "Only xml files can be uploaded.";
                    } else {
                        FileUpload1.SaveAs(this.Server.MapPath("TestData.xml"));
                        Label1.Text = "File Uploaded: " + FileUpload1.FileName;
                    }

                } else {
                    Label1.Text = "No File to Uploaded.";
                }
            } catch (Exception ex) {
                Label1.Text =
                        "An error occured while uploading or parsing the xml file. Only xml files can be uploaded.";
            }
        }