Ajax实现三级联动下拉框

jsp的代码：



<%
@ page contentType
=

"
text/html; charset=GBK
"

import
=
"
java.util.*,com.wehave.hyerp.procurement.domain.Cgsqd
"
%>



<%
@ taglib uri
=
"
struts-html
"
prefix
=
"
html
"

%>



<%
@ taglib uri
=
"
struts-logic
"
prefix
=
"
logic
"

%>



<%
@ taglib uri
=
"
struts-bean
"
prefix
=
"
bean
"

%>



<
html
>



<
head
>



<
title
>

</
title
>



<
link rel
=

"
stylesheet
"
type
=

"
text/css
"
href
=

"
../css/olstyle.css
"
>



<
SCRIPT type
=
"
text/javascript
"
>



var req;





window.onload
=
function()



{



}





function Change_Select()







{



var zhi
=
document.getElementById(
'
m_gykfwzlbb_lbbm
'
).value;



var url
=
"
sqdSelect.go?method=getSkill&id=
"
+
zhi;





if
(zhi
==
"
0
"
)



{



alert(
"
请选择您要察看的信息
"
);



return
;





}

else



{



if
(window.XMLHttpRequest)







{



req
=
new
XMLHttpRequest();



}

else

if
(window.ActiveXObject)







{



req
=
new
ActiveXObject(
"
Microsoft.XMLHTTP
"
);



}





if
(req)







{



req.open(
"
GET
"
,url,
true
);



req.onreadystatechange
=
callback;



req.send(
null
);



}



}



}





function Change_Select2()







{



var zhi
=
document.getElementById(
'
m_lbbm_se
'
).value;



//
alert(zhi.substring(0,2));





if
(zhi
==
"
0
"
)



{



alert(
"
请选择您要察看的信息
"
);



return
;



}





if
(zhi.substring(
0
,
2
)
==
"
WY
"
)



{



var url
=
"
sqdSelect.go?method=getSkill2&id=
"
+
zhi;



if
(window.XMLHttpRequest)







{



req
=
new
XMLHttpRequest();



}

else

if
(window.ActiveXObject)







{



req
=
new
ActiveXObject(
"
Microsoft.XMLHTTP
"
);



}





if
(req)







{



req.open(
"
GET
"
,url,
true
);



req.onreadystatechange
=
callback2;



req.send(
null
);



}





}

else



{



parent.topFram.location
=
"
sqdSelectAll.go?method=getlistAll&id=
"
+
zhi;



}



}





function Change_Select3()







{



var zhi
=
document.getElementById(
'
m_lbbm_th
'
).value;



//
alert(zhi.substring(0,2));





if
(zhi
==
"
0
"
)



{



alert(
"
请选择您要察看的信息
"
);



return
;





}

else



{



parent.topFram.location
=
"
sqdSelectAll.go?method=getlistAll2&id=
"
+
zhi;



}



}





function callback()







{



if
(req.readyState
==

4
)







{



if
(req.status
==

200
)







{



parseMessage();





}

else



{



alert(
"
Not able to retrieve description
"
+
req.statusText);



}



}



}





function callback2()







{



if
(req.readyState
==

4
)







{



if
(req.status
==

200
)







{



parseMessage2();





}

else



{



alert(
"
Not able to retrieve description
"
+
req.statusText);



}



}



}





function parseMessage()







{



var xmlDoc
=
req.responseXML.documentElement;



var xSel
=
xmlDoc.getElementsByTagName(
'
select
'
);



var select_root
=
document.getElementById(
'
m_lbbm_se
'
);



select_root.options.length
=
0
;





for
(var i
=
0
;i
<
xSel.length;i
++
)







{



var xValue
=
xSel[i].childNodes[
0
].firstChild.nodeValue;



var xText
=
xSel[i].childNodes[
1
].firstChild.nodeValue;



var option
=
new
Option(xText,xValue);





try



{



select_root.add(option);





}

catch
(e)



{



}



}



}





function parseMessage2()







{



var xmlDoc
=
req.responseXML.documentElement;



var xSel
=
xmlDoc.getElementsByTagName(
'
select
'
);



var select_root
=
document.getElementById(
'
m_lbbm_th
'
);



select_root.options.length
=
0
;





for
(var i
=
0
;i
<
xSel.length;i
++
)







{



var xValue
=
xSel[i].childNodes[
0
].firstChild.nodeValue;



var xText
=
xSel[i].childNodes[
1
].firstChild.nodeValue;



var option
=
new
Option(xText,xValue);





try



{



select_root.add(option);





}

catch
(e)



{



}



}



}









</
SCRIPT
>



</
head
>





<
body bgcolor
=

"
#C8D0D4
"
>



<
html:form action
=
"
/cgsqdNewAction.go
"
>



<
TABLE
class

=

"
cbToolbar
"
id
=

"
idToolbar
"
cellpadding
=

'
0
'
cellspacing
=

'
0
'
>



<
TR align
=

"
left
"
valign
=

"
top
"

>



<
TD NOWRAP
>&
nbsp;物
质类别:
&
nbsp;
&
nbsp;



<
html:select property
=
"
m_gykfwzlbb_lbbm
"
onchange
=
"
Change_Select()
"
>



<
html:option value
=
"
0
"
>
请选择
</
html:option
>



<
html:options collection
=
"
LbfList
"
property
=
"
m_gykfwzlbb_lbbm
"
labelProperty
=
"
m_gykfwzlbb_lbmc
"
/>



</
html:select
>

&
nbsp;



<
html:select property
=
"
m_lbbm_se
"
styleId
=
"
m_lbbm_se
"
onchange
=
"
Change_Select2()
"
>



<
html:option value
=
"
0
"
>&
nbsp;
&
nbsp;
&
nbsp;
</
html:option
>



</
html:select
>



<
html:select property
=
"
m_lbbm_th
"
styleId
=
"
m_lbbm_th
"
onchange
=
"
Change_Select3()
"
>



<
html:option value
=
"
0
"
>&
nbsp;
&
nbsp;
&
nbsp;
</
html:option
>



</
html:select
>





</
TD
>





</
tr
>



</
table
>



</
html:form
>



</
body
>



</
html
>



action中的代码：





/** */
/**



*



* 查询物质编码类别列表操作(一级)



*
*/



public
ActionForward doSelectWzlb(



ActionMapping mapping,



ActionForm form,



HttpServletRequest req,





HttpServletResponse res)



{



HttpSession session
=
req.getSession();



UserSession userSession
=



(UserSession) session.getAttribute(
"
userSession
"
);



permission.setUserID(userSession.getUserId());



permission.setUserName(userSession.getUserName());



permission.setModuleName(
"
m_cgsqd
"
);



permission.setActionStr(
"
'm_select'
"
);





if
(permissionService.checkUserPermission(permission))



{



int
updateSign
=
0
;





try



{



cgsqdService.updateCgsqwzhzb_sqsl();



updateSign
=
1
;





}

catch
(Exception e)



{



e.printStackTrace();



updateSign
=
0
;



}





if
(updateSign
==
1
)



{



List LbfList
=
cgsqdService.treeListWzlb2();



req.setAttribute(
"
LbfList
"
,LbfList);



return
mapping.findForward(
"
tools
"
);





}

else



{



return

null
;



}





}

else



{



return
mapping.findForward(
"
failure
"
);



}



}







/** */
/**



*



* 查询物质编码类别列表操作(二级)



*
*/



public
ActionForward doSelectWzlb1(



ActionMapping mapping,



ActionForm form,



HttpServletRequest req,





HttpServletResponse res)



{



HttpSession session
=
req.getSession();



UserSession userSession
=



(UserSession) session.getAttribute(
"
userSession
"
);



permission.setUserID(userSession.getUserId());



permission.setUserName(userSession.getUserName());



permission.setModuleName(
"
m_cgsqd
"
);



permission.setActionStr(
"
'm_select'
"
);





if
(permissionService.checkUserPermission(permission))



{



int
updateSign
=
0
;





try



{



cgsqdService.updateCgsqwzhzb_sqsl();



updateSign
=
1
;





}

catch
(Exception e)



{



e.printStackTrace();



updateSign
=
0
;



}





if
(updateSign
==
1
)



{



List LbfList
=
cgsqdService.treeListWzlb2();



req.setAttribute(
"
LbfList
"
,LbfList);



return
mapping.findForward(
"
tools1
"
);





}

else



{



return

null
;



}





}

else



{



return
mapping.findForward(
"
failure
"
);



}



}







/** */
/**



*



* 查询物质编码类别列表操作(三级)



*
*/



public
ActionForward getSkill(



ActionMapping mapping,



ActionForm form,



HttpServletRequest req,





HttpServletResponse res)



{



HttpSession session
=
req.getSession();



UserSession userSession
=



(UserSession) session.getAttribute(
"
userSession
"
);



permission.setUserID(userSession.getUserId());



permission.setUserName(userSession.getUserName());



permission.setModuleName(
"
m_cgsqd
"
);



permission.setActionStr(
"
'm_select'
"
);





if
(permissionService.checkUserPermission(permission))



{



String id
=
req.getParameter(
"
id
"
);





res.setContentType(
"
text/xml;charset=GBK
"
);



res.setHeader(
"
Cache-Control
"
,
"
no-cache
"
);



String xml_start
=
"
<?xml version=/
"
1.0
/
"
encoding=/
"
GBK/
"
?>
"
;



xml_start
+=
"
<selects>
"
;



String xml_end
=
"
</selects>
"
;



String xml
=
"
<select><value>0</value><text>
请选择</text></select>
"
;



String m_lbbm_se
=
""
;



String m_lbmc_se
=
""
;



List LbfList
=
null
;





if
(id.equals(
"
WY
"
))



{



LbfList
=
cgsqdService.treeListWzlb3_2(id);





}

else



{



LbfList
=
cgsqdService.treeListWzlb3_1(id);



}



Iterator it
=
LbfList.iterator();





while
(it.hasNext())



{



Cgsqd cgsqd
=
(Cgsqd)it.next();



m_lbbm_se
=
cgsqd.getM_gykfwzlbb_lbbm();



m_lbmc_se
=
cgsqd.getM_gykfwzlbb_lbmc();



xml
+=
"
<select><value>
"
+
m_lbbm_se
+
"
</value><text>
"
+
m_lbmc_se
+
"
</text></select>
"
;



}



String last_xml
=
xml_start
+
xml
+
xml_end;



logger.debug(
"
XML是：
"
+
last_xml);





try



{



res.getWriter().write(last_xml);





}

catch
(IOException e)



{



e.printStackTrace();



}



return

null
;





}

else



{



return

null
;



}



}

主要代码就这些，去掉一些权限大代码，真正的代码并不多。