Hi ,How to get data from object source to report viewer..

Question

Hi,i am developing one application .In that for value in list box i m getting using object source.I need to compare these object source data to data and get the result into reportviewer ..I doing mistake some where .i m placing the code below ..pleas uggest some solution.
i have a list box and a button .i placing the button click event code here...to get data into list box i m using object source..

string thisConnectionString =
    ConfigurationManager.ConnectionStrings[
    "DatabaseConnectionString"].ConnectionString;
        string strddl = ObjectDataSource1.ToString();

       
        SqlConnection Con = new SqlConnection(thisConnectionString);

        SqlCommand Cmd = new SqlCommand("select * from table3 where [col1] ='" + strddl + "'", Con);
        SqlDataAdapter da = new SqlDataAdapter(Cmd);
        System.Data.DataSet ds = new System.Data.DataSet();
        da.Fill(ds);

        ReportDataSource datasource = new ReportDataSource("DatabaseDataSet_table3", ds.Tables[0]);
       
        ReportViewer1.LocalReport.DataSources.Clear();
        ReportViewer1.LocalReport.DataSources.Add(datasource);

        if (ds.Tables[0].Rows.Count == 0)
        {
            // lblMessage.Text = "Sorry, no data under this category!";
        }

        ReportViewer1.LocalReport.Refresh();