Populating multiple user controls from a database

Question

I need to populate some user controls in a group box (from a database) based on what the user selects in one of the controls.

Each control is to be populated by a column from a table in a database. The values are occasionally null, sometimes strings, and sometimes integers. The query will return only one row of data.

The group box contains many different types of controls; however, I only need to populate the read only text boxes.

Below is how I went about solving this. My code works, but seems clunky to me. IE. nested try/catch and nested loops/conditional statements.

Is there a simpler/better/cleaner way to accomplish this?

ERPDB.sqlGetDataReader returns takes a sql statement string as an argument and returns a OracleDataReader .

sqlString takes a the user input from a user control and returns aa sql query as a string with multiple columns.

 private void populateReadOnlyColumns()
    {
        OracleDataReader dr = ERPDB.sqlGetDataReader(sqlString(userSelection));
        while (dr.Read())
        {
            int i = 0;
            foreach (Control control in groupBox1.Controls)
            {
                if( control is TextBox)
                {
                    TextBox txtBox = (TextBox)control;
                    if (txtBox.ReadOnly == true)
                    {
                        safeString(dr, txtBox, i);
                        i++;
                    }
                }
            }
        }
    }

private void safeString(OracleDataReader dr, Control control, int index)
{
    try
    {
        try
        {
            control.Text = dr.GetString(index);
        }
        catch
        {
            control.Text = Convert.ToString(dr.GetInt32(index));                                        
        }
    }
    catch
    {
        control.Text = "";
    }
}



private string sqlString(string userSelection)
        {
            StringBuilder sb = new StringBuilder();
            sb.AppendLine("SELECT description");
            sb.AppendLine("       ,job_title");    
            sb.AppendLine("       ,category");
            sb.AppendLine("       ,risk_code");
            sb.AppendLine("       ,exempt_flag");
            sb.AppendLine("       ,pay_grade");        
            sb.AppendLine("  FROM emp_jobs");   
            sb.AppendLine(" WHERE job_code = '" + userSelection.Trim() + "'");
            return sb.ToString();
        }

Answer 1

Well one way you can make it simpler/cleaner is by using LINQ:

int i = 0;
foreach (TextBox txtBox in (from Control control in groupBox1.Controls
                            where control is TextBox && ((TextBox)control).ReadOnly
                            select control))
    safeString(dr, txtBox, i++);