In this article I will explain with an example, how to set ListBox selected value from SQL Server database in ASP.Net MVC.
Note: For beginners in ASP.Net MVC, please refer my article ASP.Net MVC Hello World Tutorial with Sample Program example.
 
 

Database

I have made use of the following table Hobbies with the schema as follow.
ASP.Net MVC: Set ListBox selected value from Database
 
I have already inserted few records in the table.
ASP.Net MVC: Set ListBox selected value from Database
 
Note: You can download the database table SQL by clicking the download link below.
          Download SQL file
 
 

Namespaces

You will need to import the following namespaces.
using System.Data.SqlClient;
using System.Configuration;
 
 

Controller

The Controller consists of following Action method.

Action Method for handling GET operation

Inside this Action method, first the generic List collection of SelectListItem class object is created and connection is read from the Web.Config file.
Note: For more details on how to read connection string from Web.Config file, please refer my article Read or Write Connection Strings in Web.Config file using ASP.Net using C# and VB.Net.
 
A connection to the database is established using the SqlConnection class.
Then, using ExecuteReader method, the records are fetched from the Hobbies Table and set to the respective properties of SelectListItem class object.
Note: For more details on how to use ExecuteReader, please refer my article Using SqlCommand ExecuteReader Example in ASP.Net with C# and VB.Net.
 
Finally, the SelectListItem class object is added to the Generic List collection of SelectListItem class object which finally returned to the View.
public class HomeController : Controller
{
    // GET: Home
    public ActionResult Index()
    {
        List<SelectListItem> hobbies = new List<SelectListItem>();
        string sql = "SELECT HobbyId, Hobby, IsSelected FROM Hobbies";
        string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        using (SqlConnection con = new SqlConnection(constr))
        {
            using (SqlCommand cmd = new SqlCommand(sql, con))
            {
                con.Open();
                using (SqlDataReader sdr = cmd.ExecuteReader())
                {
                    while (sdr.Read())
                    {
                        SelectListItem item = new SelectListItem();
                        // Set the Text.
                        item.Text = sdr["Hobby"].ToString();
                        // Set the Value.
                        item.Value = sdr["HobbyId"].ToString();
                        // Set the Selected value.
                        item.Selected = Convert.ToBoolean(sdr["IsSelected"]);
                        hobbies.Add(item);
                    }
                }
                con.Close();
            }
        }
 
        return View(hobbies);
    }
}
 
 

View

HTML Markup
Inside the View, first the Generic List collection of SelectListItem class is declared Model.
The View consists of a ListBox element created using Html.ListBox Helper method.
@model List<SelectListItem>
 
@{
    Layout = null;
}
 
<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>Index</title>
</head>
<body>
    Hobbies:
    <br />
    @Html.ListBox("Hobbies", Model)
</body>
</html>
 
 

Screenshot

ASP.Net MVC: Set ListBox selected value from Database
 
 

Demo

View Demo
 
 

Downloads

Download Code