ループ内で挿入ストアドプロシージャを実行するベスト/適切な方法C＃

Question

foreachループを使用してレコードを挿入するストアドプロシージャを適切に実行するのが最適です。

これまで私がこれまで持っていたことは次のとおりです。このようにそれをやって

string constr = ConfigurationManager.ConnectionStrings["CurrencyDb"].ConnectionString; 

    using (SqlConnection con = new SqlConnection(constr)) { 
    con.Open(); 
     foreach (ListItem i in DependenciesListBox.Items) { 
      if (i.Selected) { 
       using (SqlCommand cmd = new SqlCommand("dbo.InsertDependency", con)) { 
        try { 
         cmd.CommandType = CommandType.StoredProcedure; 
         cmd.Parameters.AddWithValue("@CurrencyId", scopeidentity); 
         cmd.Parameters.AddWithValue("@DependencyId", i.Value); 
         cmd.ExecuteNonQuery(); 
        } 
        catch (SqlException sqlex) { 
         throw new Exception("SQL Exception on insert. " + sqlex.Message); 
        } 
        catch (Exception ex) { 
         throw new Exception("Error adding dependencies. " + ex.Message); 
        } 
       } 
      } 
     } 

     foreach (ListItem i in AffectedListBox.Items) { 
      if (i.Selected) { 
       using (SqlCommand cmd = new SqlCommand("dbo.InsertAffected", con)) { 
        try { 
         cmd.CommandType = CommandType.StoredProcedure; 
         cmd.Parameters.AddWithValue("@DependencyId", scopeidentity); 
         cmd.Parameters.AddWithValue("@CurrencyId", i.Value); 
         cmd.ExecuteNonQuery(); 
        } 
        catch (SqlException sqlex) { 
         throw new Exception("SQL Exception on insert. " + sqlex.Message); 
        } 
        catch (Exception ex) { 
         throw new Exception("Error adding affected apps. " + ex.Message); 
        } 
       } 
      } 
     } 

     //Loops through Platform list box and for each item that's selected, add a record into the platform table in the database. 
     foreach (ListItem i in PlatformListBox.Items) { 
      if (i.Selected) { 
       using (SqlCommand cmd = new SqlCommand("dbo.InsertPlatform", con)) { 
        try { 
         cmd.CommandType = CommandType.StoredProcedure; 
         cmd.Parameters.AddWithValue("@CurrencyId", scopeidentity); 
         cmd.Parameters.AddWithValue("@PlatformId", i.Value); 
         cmd.ExecuteNonQuery(); 
        } 
        catch (SqlException sqlex) { 
         throw new Exception("SQL Exception on insert. " + sqlex.Message); 
        } 
        catch (Exception ex) { 
         throw new Exception("Error adding platforms. " + ex.Message); 
        } 
       } 
      } 
     } 
    } 

、私は誰も私にはベストプラクティスは、この種のものをやって何のためにあるのか知っているようすることができるだろう、次のエラー（更新）

Uncaught Error: Sys.WebForms.PageRequestManagerServerErrorException: Error adding dependencies. The connection was not closed. The connection's current state is open. 
    at Function.Error.create (MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81:1) 
    at Sys.WebForms.PageRequestManager._createPageRequestManagerServerError (MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81:1) 
    at Sys.WebForms.PageRequestManager._parseDelta (MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81:1) 
    at Sys.WebForms.PageRequestManager._onFormSubmitCompleted (MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81:1) 
    at Array.<anonymous> (MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81:1) 
    at MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81:1 
    at Sys.Net.WebRequest.completed (MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81:1) 
    at XMLHttpRequest._onReadyStateChange (MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81:1) 

を取得しますか？事前にありがとうございます。

Answer 1

con.Open();に複数回電話をかけないでください。テキストではなく画像としてあなたのエラーメッセージを追加してください

https://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlconnection.open(v=vs.110).aspx