Let’s look at the HTML first. Let’s quote Jquery and put two DropDownLists:
Then write the core Script:
Very simple, check if the value is 0, and then pass the value to the server via ajax. After success, remove the original option and append the new option.
Look at the code of WebPage:
public partial class _Default: System.Web.UI.Page
{
[WebMethod]
public static List FetchEmployeeCars(int id)
{
var emp = new EmployeeCar();
return emp.FetchEmployeeCars(id);
}
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
var employees = new Employee();
ddlEmployee. DataSource = employees.FetchEmployees();
ddlEmployee.DataTextField = "Surname";
ddlEmployee.DataValueField = "Id";
ddlEmployee.DataBind();
}
}
}
Our Datasource class:
public class EmployeeCar
{
public int Id { get; set; }
public string Car { get; set; }
private static List LoadData()
{
return new List
{
new EmployeeCar {Id = 1, Car = "Ford"},
new EmployeeCar {Id = 1, Car = "Holden"},
new EmployeeCar {Id = 1, Car = "Honda"},
new EmployeeCar {Id = 2, Car = "Toyota"},
new EmployeeCar {Id = 2, Car = "General Motors"},
new EmployeeCar {Id = 2, Car = "Volvo"},
new EmployeeCar {Id = 3, Car = "Ferrari"},
new EmployeeCar {Id = 3, Car = "Porsche"},
new EmployeeCar {Id = 3, Car = "Ford2"}
};
}
public List FetchEmployeeCars(int id)
{
return (from p in LoadData()
where p.Id == id
select p).ToList();
}
}
public class Employee
{
public int Id { get; set; }
public string GivenName { get; set; }
public string Surname { get; set; }
public List FetchEmployees()
{
return new List
{
new Employee {Id = 1, GivenName = "Tom", Surname = "Hanks"},
new Employee {Id = 2, GivenName = "Hugh", Surname = "Jackman"},
new Employee {Id = 3, GivenName = "Petter", Surname = "Liu"}
};
}
public Employee FetchEmployee(int id)
{
var employees = FetchEmployees();
return (from p in employees
where p.Id == id
select p).First();
}
}
完了。希望这篇POST对您有帮助。