//C# Windows Form, when working with ComboBox, you have to assign DataSource, ValueMember to access the id of selected text and DisplayMember to show the selected text. You can achieve this using the following code:
public class Operator
{
public string Id { get; set; }
public string Sign { get; set; }
}
IList<Operator> Operators = new List<Operator>();
Operators.Add(new Operator() { Id = "1", Sign = "+" });
Operators.Add(new Operator() { Id = "2", Sign = "-" });
Operators.Add(new Operator() { Id = "3", Sign = "*" });
Operators.Add(new Operator() { Id = "4", Sign = "/" });
comboBox.DataSource = Operators;
comboBox.ValueMember = "Id";
comboBox.DisplayMember = "Sign";
switch (comboBox.SelectedValue)
{
case "1":
break;
case "2":
break;
case "3":
break;
case "4":
break;
}