I can't get the textBox_name text and listBox_order items to display correctly in one line on another listbox

Question

I have 3 list boxes, the listBox_menu is where the items are first displayed if buttons (entrees, drinks, and sides) are clicked, then to add the items to order you select your item from the listBox_menu and click add to order to have it appear in the listBox_order. From there once the customer order is ready to be made the submit button will print out the customers name (textBox_name) and all the items in the listBox_order, and display it all in one line.

I'm just having trouble figuring out how to do that, if anyone could please help.

Answer 1

First define two global variables, then use the CalculateTotalCost function (which I defined).

My answer has been updated.

Output (tested in Visual Studio 2017, .Net Framework 4.5.2):

These are my codes:

    public Form1()
    {
        InitializeComponent();
        listBox_menu.SelectionMode = SelectionMode.MultiExtended;
    }
    double Cost = 0;
    string Order = null;
    public double CalculateTotalCost(object input, bool Total)
    {
        if (Total == true)
        {
            switch (input)
            {
                case "Salad":
                    Cost += 2500;
                    break;
                case "Rice":
                    Cost += 3000;
                    break;
                case "non-alcoholic beer":
                    Cost += 1000;
                    break;
                case "Water":
                    Cost += 200;
                    break;
                case "Ex1":
                    Cost += 2200;
                    break;
                default:
                    Cost += 2200;
                    break;
            }
        }
        else
        {
            switch (input)
            {
                case "Salad":
                    Cost -= 2500;
                    break;
                case "Rice":
                    Cost -= 3000;
                    break;
                case "non-alcoholic beer":
                    Cost -= 1000;
                    break;
                case "Water":
                    Cost -= 200;
                    break;
                case "Ex1":
                    Cost -= 2200;
                    break;
                default:
                    Cost -= 2200;
                    break;
            }
        }
        return Cost;
    }
    private void Entrees_Click(object sender, EventArgs e)
    {
        listBox_menu.Items.Clear();
        listBox_menu.Items.Add("Salad");
        listBox_menu.Items.Add("Rice");
    }
    private void Drinks_Click(object sender, EventArgs e)
    {
        listBox_menu.Items.Clear();
        listBox_menu.Items.Add("non-alcoholic beer");
        listBox_menu.Items.Add("Water");
    }
    private void Sides_Click(object sender, EventArgs e)
    {
        listBox_menu.Items.Clear();
        listBox_menu.Items.Add("Ex1");
        listBox_menu.Items.Add("Ex2");
    }
    private void AddtoOrder_Click(object sender, EventArgs e)
    {
        if(listBox_menu.SelectedItems.Count>0)
        {
            for (int i = 0; i < listBox_menu.SelectedItems.Count; i++)
            {
                listBox_order.Items.Add(listBox_menu.SelectedItems[i].ToString());
                lblTotalCost.Text = (CalculateTotalCost(listBox_menu.SelectedItems[i].ToString(),true)).ToString();
            }
        }
    }
    private void RemoveFromOrder_Click(object sender, EventArgs e)
    {
        if (listBox_order.SelectedItems.Count > 0)
        {
            listBox_order.Items.Remove(listBox_order.SelectedItem);
        }
        Order = null;
        for (int i = 0; i < listBox_order.Items.Count; i++)
        {
            Order += listBox_order.Items[i].ToString() + " , ";
        }
        Cost = 0;
        if (listBox_order.Items.Count > 0)
        {
            for (int i = 0; i < listBox_order.Items.Count; i++)
            {
                Cost = (CalculateTotalCost(listBox_order.Items[i], true));
            }
        }
        lblTotalCost.Text = Cost.ToString();
    }
    private void Submit_Click(object sender, EventArgs e)
    {
        MessageBox.Show("Customer name: " + txtBoxCustomerName.Text + " Orders: " + Order + " Total cost: " + Cost);
    }