C# Binding multiple textboxes to database

Question

I'm trying to Bind 3 textboxes to a Class that retrieves any previously stored records for each of the 3 textboxes. I don't know how to retrieve 3 different values from a class in a Object Orientated perspective. I know how to return single strings, bool, etc vars but not more than 1 at a time.

example of a simple bool returning method I use, how do I adjust it to return 3 separate string variables - Code Snippet:

public static Boolean isQuestionnaireComplete(string strHash)
        {
            SqlConnection con = Sql.getConnection();

            try
            {
                SqlCommand cmd = new SqlCommand("SELECT IsComplete FROM UserDetails WHERE Hash='" + strHash + "' AND IsComplete=1");
                cmd.Connection = con;
                DataTable dt = new DataTable();
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                con.Open();
                da.Fill(dt);
                if (dt.Rows.Count == 0)
                {
                    return false;
                }
                else
                {
                    return true;
                }
            }
            catch
            {
                //TODO:log error
                return false;
            }
            finally
            {
                con.Close();
            }
        }

ASPX Snippet:

<asp:TextBox runat="server" ID="txt1" Height="200px" Width="600px"></asp:TextBox>
<asp:TextBox runat="server" ID="txt2" Height="200px" Width="600px"></asp:TextBox>
<asp:TextBox runat="server" ID="txt3" Height="200px" Width="600px"></asp:TextBox>

Answer 1

You would need to return your own structure with the 3 values. You can do an array, but you have to make sure you know which item in the array matches the textbox with a data structure you don't have, to remember [0] == the first textbox, and you can use friendly names for more readability and easier to maintain.

public static MyDataStructure isQuestionnaireComplete(string strHash)
{
    SqlConnection con = Sql.getConnection();

    try
    {
        SqlCommand cmd = new SqlCommand("SELECT IsComplete, FirstString, SecondString, ThridString FROM UserDetails WHERE Hash='" + strHash + "' AND IsComplete=1");
        cmd.Connection = con;
        DataTable dt = new DataTable();
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        con.Open();
        da.Fill(dt);

        if (dt.Rows.Count == 0)
        {
            return null;
        }
        else
        {
            // Populate object from data table
            DataRow row = dt.Rows[0];

            retun new MyDataStructure
              {
                MyFirstString = row["FirstString"],
                MySecondString = row["SecondString"],
                MyThirdString = row["ThridString"]
              };
        }
    }
    catch
    {
        //TODO:log error
        return false;
    }
    finally
    {
        con.Close();
    }
}

public class MyDataStructure
{
  public string MyFirstString { get; set; }
  public string MySecondString { get; set; }
  public string MyThirdString { get; set; }
}

Answer 2

I want to preface this with I don't quite know what you are trying to do. Is the questionaire always 3 questions? or is the size dynamic?

I would use a Repeater if the size is dynamic (this is the example I provide) or I would use a FormView if the size is fixed at 3.

Use the following code to access the database:

namespace BLL
{
    using System;
    using System.Data;
    using System.Data.SqlClient;
    [System.ComponentModel.DataObject]
    public class QuestionnaireDataObject
    {
        public static DataTable isQuestionnaireComplete(string strHash1, string strHash2, string strHash3)
        {
            DataTable dt = new DataTable();
            using (SqlConnection con = Sql.getConnection())
            {
                SqlCommand cmd =
                    new SqlCommand(
                        String.Format("SELECT Hash, IsComplete FROM UserDetails WHERE Hash IN ('{0}', '{1}', '{2}')",
                                      strHash1, strHash2, strHash3));
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                da.Fill(dt);
                da.Dispose();
            }

            return dt;
        }
    }
}

In your code behind you will need something like the following:

<asp:Repeater id="Repeater1" runat="server" datasourceid="ObjectDataSource1">
    <ItemTemplate>
        <asp:CheckBox id="CheckBox1" runat="server" checked='<%# Bind("IsComplete") %>' /><asp:TextBox
            id="TextBox1" runat="server" text='<%# Bind("Hash") %>'></asp:TextBox>
    </ItemTemplate>
</asp:Repeater>
<asp:ObjectDataSource id="ObjectDataSource1" runat="server" selectmethod="isQuestionnaireComplete"
    typename="Bll.QuestionnaireDataObject" onselecting="ObjectDataSource1_Selecting"></asp:ObjectDataSource>

And then in your code behind you will need the selecting method to set the parameters for the query:

protected void ObjectDataSource1_Selecting(object sender, ObjectDataSourceSelectingEventArgs e)
{
    e.InputParameters["strHash1"] = strHash1Value;
    e.InputParameters["strHash2"] = strHash2Value;
    e.InputParameters["strHash3"] = strHash3Value;
}

If you explain the situation a little more (What all is needed to display, and the database logic involved) I will refine my answer to closer match your needs. I hope this is a good starting point.

Answer 3

What do you want to return?

public static string[] ReturnStringArrayMethod()
{
     string[] arrStr = new string[3]();
     arrStr[0] = "first string";
     arrStr[1] = "second string";
     arrStr[2] = "third string";
     return arrStr;
}

You can do the same with and Type eg bool[], int[] etc you then access items from the return value using

string val = arrStr[0];

Answer 4

Store the strings in a dataset or a datareader then pass them back to your appropriate tier.