showing error connection property is not initialized........

 public void connect()
      {
          SqlConnection con = new SqlConnection(@"Data Source=CSZ-PCS43132\SQLEXPRESS;Initial Catalog=Test;Integrated Security=True");
          con.Open();
      }

public string viewdetails(HRViewpagedetailsMDL  objEditListingPage)
        {
            connect();
            SqlCommand cmd = new SqlCommand();
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.CommandText = "SP_USERPROFILE_INSERT";
            cmd.Parameters.AddWithValue("@firstname",objEditListingPage.firstName);
            cmd.Parameters.AddWithValue("@lastname", objEditListingPage .lastname);
            cmd.Parameters.AddWithValue("@email", objEditListingPage .email);
            cmd.Parameters.AddWithValue("@newrecruit",objEditListingPage .newrecruit);
            cmd.Parameters.AddWithValue("@siteid", objEditListingPage.site.siteid);
            cmd.Parameters.AddWithValue("@comments", objEditListingPage.comments);
            cmd.Parameters.AddWithValue("@manageothers", objEditListingPage.manageothers);
            cmd.Parameters.AddWithValue("@topfunctionid", objEditListingPage.topfunction.topfunctionid);
            cmd.Parameters.AddWithValue("@subfunctionid", objEditListingPage.subfunction.subfunctionid);
            cmd.Parameters.AddWithValue("@lmsroleid", objEditListingPage.lmsrole.lmsroleid);
            cmd.Parameters.AddWithValue("@channelid", objEditListingPage.channel.channelid);
            cmd.Parameters.AddWithValue("@employmentstatusid", objEditListingPage.employmentstatus.employmentstatusid);
            cmd.Parameters.AddWithValue("@statusid", objEditListingPage.status.statusid);
            cmd.Parameters.AddWithValue("@active", objEditListingPage.active);
            cmd.Parameters.AddWithValue("@audiencefunctionallmsid", objEditListingPage.audiencefunctionallms);
            cmd.Parameters.AddWithValue("@audiencelmsspecial", objEditListingPage.audiencespeciallms);
            cmd.Parameters.AddWithValue("@existingthecompany", objEditListingPage.existingthecompany);
            cmd.Parameters.AddWithValue("@localjobtitle", objEditListingPage.localjobtitle);
            cmd.Parameters.AddWithValue("@locallanguagejobtitle", objEditListingPage.locallanguagejobtitle);
            cmd.Parameters.AddWithValue("@kmlevel", objEditListingPage.kmlevel);
            return cmd.ExecuteNonQuery().ToString();
           
}