Jquery实现无刷新DropDownList联动实现代码

【 tulaoshi.com - Web开发 】

先看HTML,我们引用Jquery,放两个DropDownList:

代码如下：

（本文来源于图老师网站，更多请访问http://www.tulaoshi.com/webkaifa/）（本文来源于图老师网站，更多请访问http://www.tulaoshi.com/webkaifa/）
style type="text/css"
#ddlEmployeeCars
{
display:none;
position:absolute;
top:50px;
left:9px;
}
/style
script language="javascript" type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"/script

　　 asp:DropDownList runat="server" AppendDataBoundItems="true"
asp:ListItem Text="(Please Select)" Value="0" Selected="True" /
/asp:DropDownList
asp:DropDownList runat="server"
/asp:DropDownList

接着写核心的Script:

代码如下：

（本文来源于图老师网站，更多请访问http://www.tulaoshi.com/webkaifa/）（本文来源于图老师网站，更多请访问http://www.tulaoshi.com/webkaifa/）
script language="javascript" type="text/javascript"
$(function() {
var $ddl = $("select[name$=ddlEmployee]");
var $ddlCars = $("select[name$=ddlEmployeeCars]");
$ddl.focus();
$ddl.bind("change keyup", function() {
if ($(this).val() != "0") {
loadEmployeeCars($("select option:selected").val());
$ddlCars.fadeIn("slow");
} else {
$ddlCars.fadeOut("slow");
}
});
});

function loadEmployeeCars(selectedItem) {
$.ajax({
type: "POST",
url: "Default.aspx/FetchEmployeeCars",
data: "{id: " + selectedItem + "}",
contentType: "application/json; charset=utf-8",
dataType: "json",
async: true,
success: function Success(data) {
printEmployeeCars(data.d);
}
});
}

function printEmployeeCars(data) {
$("select[name$=ddlEmployeeCars] option").remove();
for (var i = 0; i data.length; i++) {
$("select[name$=ddlEmployeeCars]").append(
$("option/option").val(data[i].Id).html(data[i].Car)
);
}
}
/script

非常简单，检查值是不是０，然后ajax传值到server，成功后remove掉原来的option,append新的option.
看下WebPage的code:

代码如下：

（本文来源于图老师网站，更多请访问http://www.tulaoshi.com/webkaifa/）（本文来源于图老师网站，更多请访问http://www.tulaoshi.com/webkaifa/）
public partial class _Default : System.Web.UI.Page
{
[WebMethod]
public static ListEmployeeCar 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();
}
}
}

我们的Datasource class:

代码如下：

（本文来源于图老师网站，更多请访问http://www.tulaoshi.com/webkaifa/）（本文来源于图老师网站，更多请访问http://www.tulaoshi.com/webkaifa/）
public class EmployeeCar
{
public int Id { get; set; }
public string Car { get; set; }

private static ListEmployeeCar LoadData()
{
return new ListEmployeeCar
{
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 ListEmployeeCar 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 ListEmployee FetchEmployees()
{
return new ListEmployee
{
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。