Re: dynamic Filter ( Using multiple drop down list)

Good morning Wim,

I hope that I am not confusing. I  am not trying to say your original piece of code is not working. I am debugging the code and I am visually seeing the code is crashing. I am providing the complete function in order to have a big picture . It should populate the data based on the parameters that I am sending from the code behind. 

protected bool GetData(DateTime start, DateTime end, string campaign)
            {
            bool flag = false;
            OleDbConnection connection = null;
            OleDbCommand selectCommand = null;
            OleDbDataAdapter adapter = null; DataSet dataSet = new DataSet(); //DataSet dataSet = null; 
            string str = base.Request.QueryString["OB"];
            string str2 = base.Request.QueryString["Alias"];
            string cObAlias = "";
            if (string.IsNullOrEmpty(str))
                {
                str = ConfigurationManager.AppSettings["ObjectBroker"];
                }
            string obConnectionString = AmAccess.GetObConnectionString(str, ref cObAlias);
            try
                {
                connection = new OleDbConnection(obConnectionString);
                connection.Open();
                selectCommand = new OleDbCommand("clients.dbo.spx_AmountStatsReport11", connection)
                    {
                    CommandType = CommandType.StoredProcedure,
                    CommandTimeout = connection.ConnectionTimeout
                    };
                selectCommand.Parameters.AddWithValue("@start", start);
                selectCommand.Parameters.AddWithValue("@end", end);
                if (string.IsNullOrEmpty(campaign))
                    {
                    if (this.ddlCampaigns.SelectedItem.Text == "All")
                        {
                        selectCommand.Parameters.AddWithValue("@campaignId", DBNull.Value);
                        selectCommand.Parameters.AddWithValue("@campaign", DBNull.Value);
                        selectCommand.Parameters.AddWithValue("@segment", DBNull.Value);
                        selectCommand.Parameters.AddWithValue("@downloadDescriptions", DBNull.Value);
                        }
                    else
                        {
                        string s = "@segment";  // either s = "@segment = " or s = "@segment"// both does not work
                        // get selected segments
                        int[] selectedsegments = lbSegments.GetSelectedIndices();
                        // add selected segments to s
                        for (int cnt = 0; cnt < selectedsegments.Length; cnt++)
                            {
                            s += lbSegments.Items[selectedsegments[cnt]].Text + ",";   // by finishing this line, codes will crash immediately.
                            }

                        // display

                        selectCommand.Parameters.AddWithValue("@campaignId", this.ddlCampaigns.SelectedValue);
                        selectCommand.Parameters.AddWithValue("@campaign", DBNull.Value);
                        selectCommand.Parameters.AddWithValue("@segment", s);
                       }
                    }
                else if (campaign == "All")
                    {
                    selectCommand.Parameters.AddWithValue("@campaignId", DBNull.Value);
                    selectCommand.Parameters.AddWithValue("@campaign", DBNull.Value);
                    selectCommand.Parameters.AddWithValue("@segment", DBNull.Value);
                    selectCommand.Parameters.AddWithValue("@downloadDescriptions", DBNull.Value);
                    }
                else
                    {
                    selectCommand.Parameters.AddWithValue("@campaignId", DBNull.Value);
                    selectCommand.Parameters.AddWithValue("@campaign", campaign);
                    selectCommand.Parameters.AddWithValue("@segment", DBNull.Value);
                    selectCommand.Parameters.AddWithValue("@downloadDescriptions", DBNull.Value);
                    }
                adapter = new OleDbDataAdapter(selectCommand);  //dataSet = new DataSet();
                adapter.Fill(dataSet);
                if (dataSet.Tables[0].Rows.Count > 0)
                    {
                    this.m_Data = "1";
                    flag = true;
                    }
                if (this.CheckConfigurationOn("RemoveTotalRows"))
                    {
                    if (dataSet.Tables[0].Rows.Count > 0)
                        {
                        dataSet.Tables[0].Rows[dataSet.Tables[0].Rows.Count - 1].Delete();
                        }
                    if (dataSet.Tables[1].Rows.Count > 0)
                        {
                        dataSet.Tables[1].Rows[dataSet.Tables[1].Rows.Count - 1].Delete();
                        }
                    }
                this.gvSummary.DataSource = dataSet.Tables[0];
                this.gvSummary.DataBind();
                this.GridView1.DataSource = dataSet.Tables[1];
                this.GridView1.DataBind();
                this.SaveColumnNames(this.gvColumnNames, dataSet.Tables[1]);
                this.SaveColumnNames(this.gvColumnNamesSummary, dataSet.Tables[0]);
                this.SetRefreshTimer();
                }
            catch (Exception exception)
                {
                this.m_Error = exception.Message;
                this.m_Error = this.m_Error + exception.StackTrace;
                this.m_Error = this.m_Error.Replace(@"\", @"\\");
                this.m_Error = this.m_Error.Replace("'", @"\'");
                this.m_Error = Regex.Replace(this.m_Error, @"\s+", " ").Trim();
                this.m_Error = base.Server.HtmlEncode(this.m_Error);
                }
            finally
                {
                dataSet.Dispose();
                dataSet = null;
                adapter.Dispose();
                adapter = null;
                selectCommand.Dispose();
                selectCommand = null;
                connection.Close();
                connection = null;
                }
            return flag;
            }

now, if I use the same function above with little bit modification to your original code, it will work only if I select a single segment. it generates the report but it will fail if I select multiple segments. it crashes. 

Here is the modification codes

//string s = "@segment";
                        string @segment = "";
                        // get selected segments
                        int[] selectedsegments = lbSegments.GetSelectedIndices();
                        // add selected segments to s
                        for (int cnt = 0; cnt < selectedsegments.Length; cnt++)
                            {
                            @segment += lbSegments.Items[selectedsegments[cnt]].Text + ",";
                            }

                        // display
                        lbSegments.Text = @segment.Trim(',');
                        selectCommand.Parameters.AddWithValue("@campaignId", this.ddlCampaigns.SelectedValue);
                        selectCommand.Parameters.AddWithValue("@campaign", DBNull.Value);
                        selectCommand.Parameters.AddWithValue(@segment, lbSegments.SelectedValue);

I was actually debugging it and I was stepping through each step and I saw exactly where it crashed. Hopefully this will make sense to you. My question is if it is working for a single select why it is crashing for multiple selects. what things should be changed to make it runs. I forgot to mention. I have changed the dataset from null to new dataset, I put it in bold in case you want to see their location.