jquery + ashx DropDownList 二级
前台：
Code
<%
@ Page Language
=
"
C#
"
AutoEventWireup
=
"
true
"
CodeFile
=
"
Default.aspx.cs
"
Inherits
=
"
_Default
"
%>
<!
DOCTYPE html PUBLIC
"
-//W3C//DTD XHTML 1.0 Transitional//EN
"
"
http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd
"
>
<
html xmlns
=
"
http://www.w3.org/1999/xhtml
"
>
<
head runat
=
"
server
"
>
<
title
></
title
>
<
script src
=
"
javascript/jquery-1.3.2.min.js
"
type
=
"
text/javascript
"
></
script
>
<
script type
=
"
text/javascript
"
>
<!--
$(function() {
$(
"
#ddlMenuOne
"
).append(
"
<option value='-1' selected='selected'>请选择...</option>
"
);
ddlMenuTwoInit();
$.getJSON(
"
DDLMenu.ashx
"
,
{ menuOneId: $(
"
#ddlMenuOne
"
).val() },
function(json) {
$.each(json, function(i) {
$(
"
#ddlMenuOne
"
).append(
"
<option value='
"
+
json[i].Id
+
"
'>
"
+
json[i].MenuOneName
+
"
</option>
"
);
});
});
$(
"
#ddlMenuOne
"
).change(function(
event
) {
if
($(
"
#ddlMenuOne
"
).val()
!==
"
-1
"
) {
$.getJSON(
"
DDLMenu.ashx
"
,
{ menuOneId: $(
"
#ddlMenuOne
"
).val() },
function(json) {
ddlMenuTwoInit();
$.each(json, function(i) {
$(
"
#ddlMenuTwo
"
).append(
"
<option value='
"
+
json[i].Id
+
"
'>
"
+
json[i].MenuTwoName
+
"
</option>
"
);
});
});
}
else
{
ddlMenuTwoInit();
}
});
});
function ddlMenuTwoInit() {
$(
"
#ddlMenuTwo
"
).html(
""
).append(
"
<option value='-1' selected='selected'>请选择...</option>
"
);
}
//
-->
</
script
>
</
head
>
<
body
>
<
form id
=
"
form1
"
runat
=
"
server
"
>
<
div
>
<
asp:DropDownList ID
=
"
ddlMenuOne
"
runat
=
"
server
"
>
</
asp:DropDownList
>
<
br
/>
<
asp:DropDownList ID
=
"
ddlMenuTwo
"
runat
=
"
server
"
>
</
asp:DropDownList
>
</
div
>
<
ul id
=
"
list
"
>
</
ul
>
</
form
>
</
body
>
</
html
>
后台 ashx
Code
<%
@ WebHandler Language
=
"
C#
"
Class
=
"
DDLMenu
"
%>
using
System;
using
System.Web;
using
System.Collections.Generic;
using
System.Web.Script.Serialization;
using
System.ServiceModel.Dispatcher;
public
class
DDLMenu : IHttpHandler
{
public
void
ProcessRequest(HttpContext context)
{
context.Response.ContentType
=
"
text/plain
"
;
int
menuOneId
=
Convert.ToInt32(context.Request.QueryString[
"
menuOneId
"
]);
JsonQueryStringConverter jq
=
new
JsonQueryStringConverter();
//
JavaScriptSerializer serializer = new JavaScriptSerializer();
//
string data = serializer.Serialize(list);
string
data
=
""
;
if
(menuOneId
==
-
1
)
{
List
<
MenuOne
>
list
=
new
List
<
MenuOne
>
();
list.Add(
new
MenuOne { Id
=
1
, MenuOneName
=
"
城市
"
});
list.Add(
new
MenuOne { Id
=
2
, MenuOneName
=
"
年份
"
});
list.Add(
new
MenuOne { Id
=
3
, MenuOneName
=
"
蔬菜
"
});
data
=
jq.ConvertValueToString(list,
typeof
(List
<
MenuOne
>
));
}
else
{
List
<
MenuTwo
>
list
=
new
List
<
MenuTwo
>
();
list.Add(
new
MenuTwo { Id
=
1
, MenuOneId
=
1
, MenuTwoName
=
"
淮安
"
});
list.Add(
new
MenuTwo { Id
=
2
, MenuOneId
=
1
, MenuTwoName
=
"
南京
"
});
list.Add(
new
MenuTwo { Id
=
3
, MenuOneId
=
1
, MenuTwoName
=
"
盐城
"
});
list.Add(
new
MenuTwo { Id
=
4
, MenuOneId
=
1
, MenuTwoName
=
"
苏州
"
});
list.Add(
new
MenuTwo { Id
=
5
, MenuOneId
=
1
, MenuTwoName
=
"
无锡
"
});
list.Add(
new
MenuTwo { Id
=
6
, MenuOneId
=
1
, MenuTwoName
=
"
镇江
"
});
list.Add(
new
MenuTwo { Id
=
7
, MenuOneId
=
1
, MenuTwoName
=
"
泰州
"
});
list.Add(
new
MenuTwo { Id
=
8
, MenuOneId
=
2
, MenuTwoName
=
"
2000
"
});
list.Add(
new
MenuTwo { Id
=
9
, MenuOneId
=
2
, MenuTwoName
=
"
2001
"
});
list.Add(
new
MenuTwo { Id
=
10
, MenuOneId
=
2
, MenuTwoName
=
"
2002
"
});
list.Add(
new
MenuTwo { Id
=
11
, MenuOneId
=
2
, MenuTwoName
=
"
2003
"
});
list.Add(
new
MenuTwo { Id
=
12
, MenuOneId
=
2
, MenuTwoName
=
"
2004
"
});
list.Add(
new
MenuTwo { Id
=
13
, MenuOneId
=
2
, MenuTwoName
=
"
2005
"
});
list.Add(
new
MenuTwo { Id
=
14
, MenuOneId
=
2
, MenuTwoName
=
"
2006
"
});
list.Add(
new
MenuTwo { Id
=
15
, MenuOneId
=
3
, MenuTwoName
=
"
黄瓜
"
});
list.Add(
new
MenuTwo { Id
=
16
, MenuOneId
=
3
, MenuTwoName
=
"
萝卜
"
});
list.Add(
new
MenuTwo { Id
=
17
, MenuOneId
=
3
, MenuTwoName
=
"
白菜
"
});
list.Add(
new
MenuTwo { Id
=
18
, MenuOneId
=
3
, MenuTwoName
=
"
猪肉
"
});
list.Add(
new
MenuTwo { Id
=
19
, MenuOneId
=
3
, MenuTwoName
=
"
鸡腿
"
});
list.Add(
new
MenuTwo { Id
=
20
, MenuOneId
=
3
, MenuTwoName
=
"
闫腾
"
});
list.Add(
new
MenuTwo { Id
=
21
, MenuOneId
=
3
, MenuTwoName
=
"
黄鱼
"
});
List
<
MenuTwo
>
newList
=
new
List
<
MenuTwo
>
();
int
n
=
list.Count;
for
(
int
i
=
0
; i
<
n; i
++
)
{
if
(list[i].MenuOneId
==
menuOneId)
newList.Add(list[i]);
}
data
=
jq.ConvertValueToString(newList,
typeof
(List
<
MenuTwo
>
));
}
context.Response.Write(data);
}
public
bool
IsReusable
{
get
{
return
false
;
}
}
}
哈哈！~