find email address in text file using c#

  string data = File.ReadAllText("filepath"); //read File

        //instantiate with this pattern

        Regex emailRegex = new Regex(@"\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*", RegexOptions.IgnoreCase);

        //find items that matches with our pattern

        MatchCollection emailMatches = emailRegex.Matches(data);

        foreach (Match emailMatch in emailMatches)

        {         

            String AnchorLink;

            AnchorLink = "<" + "a href=" + emailMatch.Value + " style="+"text-decoration:underline"+">" + emailMatch.Value + "<a>";

            lblId.Text += data.Replace(emailMatch.Value, AnchorLink);                   

        }      

Open and read an XML file to Dataset

 foreach (string file in Directory.GetFiles("write your path", "*.xml"))
            {
                if (file.Length > 0)
                {
                    dsMenu = new DataSet();
                    dsMenu.ReadXml(file);
                    DataTable dt = dsMenu.Tables[0];
                    DataTable dt2 = dsMenu.Tables[1];
                    DataTable dt3 = dsMenu.Tables[2];

                }
            }