C # MVC simple session-based recycle bin

Question

I am trying to figure out a simple basket in which products are stored in a session.

Index Type:

<table class="table">
    <tr>
        <th>
            @Html.DisplayNameFor(model => model.product1)
        </th>
        <th></th>
    </tr>

@foreach (var item in Model) {
    <tr>
        <td>
            @Html.DisplayFor(modelItem => item.product1)
        </td>
        <td>
            @Html.ActionLink("Add products to cart", "AddToBasket", new { id=item.id})
        </td>
    </tr>
}

</table>

Next to each product is "Add to Cart" to the AddToBasket method in the controller, which reads the product identifier and stores it in the session list ["cart"]:

public ActionResult AddToBasket(int? id)
{
        if (Session["Basket"] == null)
        {
            Session["Basket"] = new List<int>();
        }

        ((List<int>)Session["Basket"]).Add(id.Value);
        ViewBag.List = Session["Basket"];


        return RedirectToAction("Index");
}

Now I saved the product identifiers in the session and would like to get information from the database and match them with the identifiers. And that I can’t understand. I tried to create a dictionary and populate it with values, but obviously this did not work:

public ActionResult ShowBasket()
{
    List<int> lista = new List<int>((List<int>)Session["Basket"]);

    Dictionary<int, string> productSet = new Dictionary<int, string>();

    foreach (var product in lista)
    {
        productSet[product] = db.products.Find(product).ToString();
    }

    ViewBag.products = productSet;

    return View(slownik);
}

Also tried ADO.Net to retrieve data from the database, but failed again:

public ActionResult ShowBasket()
{
    List<int> plist = new List<int>((List<int>)Session["Basket"]);

    SqlConnection myConnection = new SqlConnection(my_connection_string);
    SqlCommand myCommand;
    SqlDataReader myReader;
    string s;

    myConnection.Open();
    s = "select product from db.products where id=" + plist[0];
    myCommand = new SqlCommand(s, myConnection);
    myReader = myCommand.ExecuteReader();
    if (myReader.Read())
    {
        string loaded_record = myReader.GetString("product1");
    }

    myConnection.Close();
    return View();
}

Can anyone help with this? I am just starting out, after a dozen hours looking for ideas that I decided to ask for help, since I can't handle it ...

!

Answer 1

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public ActionResult AddToBasket(int? id)
{
    if (Session["Basket"] == null)
    {
        Session["Basket"] = new List<int>();
    }

    var items = (List<int>)Session["Basket"];
    items.Add(id.Value);
    Session["Basket"] = items;
    ViewBag.List = Session["Basket"];

    return RedirectToAction("Index");
}

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Answer 2

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Entity Framework ADO.NET. , , , .

ADO:

public ActionResult ShowBasketADO()
    {
        List<Product> result = new List<Product>();

        List<int> plist = new List<int>((List<int>)Session["Basket"]);
        //We try to be sure that we only make a single query
        string query = "select id, descripcion from products where id in (" + string.Join(",", plist) + ")";
        //Start using IDisposable interface (yes, you can also use it for SqlCommand)
        using (SqlConnection myConnection = new SqlConnection(cnxString))
        {
            SqlCommand myCommand;
            SqlDataReader myReader;
            myConnection.Open();
            myCommand = new SqlCommand(query, myConnection);
            myReader = myCommand.ExecuteReader();
            while (myReader.Read())
            {
                Product item = new Product();
                item.Id = (int)myReader[0];
                item.Descripcion = (string)myReader[1];
                result.Add(item);
            }
            myConnection.Close();
        }

        return View(result);
    }

EF:

private ApplicationDbContext db = new ApplicationDbContext();
    public ActionResult ShowBasket()
    {

        List<int> mylist = new List<int>((List<int>)Session["Basket"]);

        List<Product> IntheCart = new List<Product>();

        foreach (var item in mylist)
        {
            IntheCart.Add(db.Productos.Find(item));

        }
       return View(IntheCart);
      }

:

@model IEnumerable<TestApp.Models.Product>
@{
    ViewBag.Title = "ShowBasket";
}
<h2>ShowBasket</h2>
<table class="table">
    <tr>
        <th>
            @Html.DisplayNameFor(model => model.Descripcion)
        </th>
        <th></th>
    </tr>
@foreach (var item in Model) {
    <tr>
        <td>
            @Html.DisplayFor(modelItem => item.Descripcion)
        </td>
        <td>
            @Html.ActionLink("Delete", "Delete", new { id=item.Id })
        </td>
    </tr>
}
</table>

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