c# - 返された SELECT 値が NULL であるか、テーブルに存在しない場合は、新しい例外を送信します

Question

だから私はストアド プロシージャを使用して DB からレジストリを選択しています。ストアド プロシージャが行う唯一のことは SELECT です。問題は、そのストアド プロシージャを使用して、WebService で返す DataSet を埋めることです。問題は、ストアド プロシージャが DB をチェックして空の行を返すため、DataSet の代わりに例外を送信したい場合に発生します。DataSet は何も入力せず、例外に送信されません。同じDBのログテーブルの例外...私の質問は、SELECT値が空の場合、例外ブロックに移動できますか??

これが私のコードです

[WebMethod(Description = "Private", EnableSession = false)]
public DataSet M812(string p_transaction)
{
    string extran, enclosure, eDate;
    try
    {
        SqlConnection con = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["CTSSQL"].ConnectionString);
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        cmd.CommandText = "dbo.sp_M812";
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Parameters.Add("@p_trans", SqlDbType.NChar, 18).Value = p_transaction;
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        DataSet ds = new DataSet();
        da.Fill(ds, "Entradas");
        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
        cmd.Connection.Close();
        return ds;
    }
    catch(SqlException Ex)
    {
        SqlConnection con = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["CTSSQL"].ConnectionString);
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        cmd.CommandText = "dbo.sp_reqdataerrorlog";
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Parameters.Add("@p_inTrans", SqlDbType.NChar, 12).Value = p_transaction;
        cmd.Parameters.Add("@vo_enclosure", SqlDbType.VarChar, 250).Direction = ParameterDirection.Output;
        cmd.Parameters.Add("@vo_trans", SqlDbType.VarChar, 10).Direction = ParameterDirection.Output;
        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
        cmd.Connection.Close();
        enclosure = "" + cmd.Parameters["@vo_enclosure"].Value;
        extran = "" + cmd.Parameters["@vo_trans"].Value;

        SqlConnection con2 = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["CTSSQL"].ConnectionString);
        SqlCommand cmd2 = new SqlCommand();
        cmd2.Connection = con2;
        cmd2.CommandText = "dbo.sp_errorlog";
        cmd2.CommandType = CommandType.StoredProcedure;
        cmd2.Parameters.Add("@p_inTrans", SqlDbType.NChar, 12).Value = p_transaction;
        cmd2.Parameters.Add("@p_enclosure", SqlDbType.NChar, 6).Value = enclosure;
        cmd2.Parameters.Add("@p_trans", SqlDbType.NChar, 18).Value = extran;
        cmd2.Parameters.Add("@p_method", SqlDbType.NChar, 6).Value = "812";
        cmd2.Parameters.Add("@p_message", SqlDbType.NVarChar, 250).Value = "SQL Error: " + Ex.Message;
        cmd2.Parameters.Add("@vo_message", SqlDbType.VarChar, 250).Direction = ParameterDirection.Output;
        cmd2.Parameters.Add("@vo_errorDate", SqlDbType.DateTime).Direction = ParameterDirection.Output;
        con2.Open();
        cmd2.ExecuteNonQuery();
        con2.Close();
        cmd2.Connection.Close();
        eDate = "" + cmd2.Parameters["@vo_errorDate"].Value;

        SqlConnection con3 = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["CTSSQL"].ConnectionString);
        SqlCommand cmd3 = new SqlCommand();
        cmd3.Connection = con3;
        cmd3.CommandText = "dbo.sp_selecterrorlog";
        cmd3.CommandType = CommandType.StoredProcedure;
        cmd3.Parameters.Add("@p_trans", SqlDbType.NChar, 18).Value = p_transaction;
        cmd3.Parameters.Add("@p_date", SqlDbType.DateTime).Value = eDate;
        SqlDataAdapter da = new SqlDataAdapter(cmd3);
        DataSet ds = new DataSet();
        da.Fill(ds, "ErrorLog");
        con3.Open();
        cmd3.ExecuteNonQuery();
        con3.Close();
        cmd3.Connection.Close();
        return ds;
    }
    catch (Exception Ex)
    {
        SqlConnection con = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["CTSSQL"].ConnectionString);
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        cmd.CommandText = "dbo.sp_reqdataerrorlog";
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Parameters.Add("@p_inTrans", SqlDbType.NChar, 12).Value = p_transaction;
        cmd.Parameters.Add("@vo_enclosure", SqlDbType.VarChar, 250).Direction = ParameterDirection.Output;
        cmd.Parameters.Add("@vo_trans", SqlDbType.VarChar, 10).Direction = ParameterDirection.Output;
        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
        cmd.Connection.Close();
        enclosure = "" + cmd.Parameters["@vo_enclosure"].Value;
        extran = "" + cmd.Parameters["@vo_trans"].Value;

        SqlConnection con2 = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["CTSSQL"].ConnectionString);
        SqlCommand cmd2 = new SqlCommand();
        cmd2.Connection = con2;
        cmd2.CommandText = "dbo.sp_errorlog";
        cmd2.CommandType = CommandType.StoredProcedure;
        cmd2.Parameters.Add("@p_inTrans", SqlDbType.NChar, 12).Value = p_transaction;
        cmd2.Parameters.Add("@p_enclosure", SqlDbType.NChar, 6).Value = enclosure;
        cmd2.Parameters.Add("@p_trans", SqlDbType.NChar, 18).Value = extran;
        cmd2.Parameters.Add("@p_method", SqlDbType.NChar, 6).Value = "812";
        cmd2.Parameters.Add("@p_message", SqlDbType.NVarChar, 250).Value = "WEB Error: " + Ex.Message;
        cmd2.Parameters.Add("@vo_message", SqlDbType.VarChar, 250).Direction = ParameterDirection.Output;
        cmd2.Parameters.Add("@vo_errorDate", SqlDbType.DateTime).Direction = ParameterDirection.Output;
        con2.Open();
        cmd2.ExecuteNonQuery();
        con2.Close();
        cmd2.Connection.Close();
        eDate = "" + cmd2.Parameters["@vo_errorDate"].Value;

        SqlConnection con3 = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["CTSSQL"].ConnectionString);
        SqlCommand cmd3 = new SqlCommand();
        cmd3.Connection = con3;
        cmd3.CommandText = "dbo.sp_selecterrorlog";
        cmd3.CommandType = CommandType.StoredProcedure;
        cmd3.Parameters.Add("@p_trans", SqlDbType.NChar, 18).Value = p_transaction;
        cmd3.Parameters.Add("@p_date", SqlDbType.DateTime).Value = eDate;
        SqlDataAdapter da = new SqlDataAdapter(cmd3);
        DataSet ds = new DataSet();
        da.Fill(ds, "ErrorLog");
        con3.Open();
        cmd3.ExecuteNonQuery();
        con3.Close();
        cmd3.Connection.Close();
        return ds;
    }

}