单击表单触发函数查数据库,然后获取值

[linsl]

<form name='myform'>

<select name="TopClassID" id="TopClassID"> 
<option selected value="">请选择省</option> 
 
<option value="1">浙江</option> 



 
</select>
市
<select name="BigClassID" id="BigClassID" > 
<option selected value="">杭州市</option> 
</select>
县
<select name="SmallClassID" id="SmallClassID" > 
<option selected value="">西湖区</option> 
</select> 

邮编:
<input type="text" value="单击查询" onclick="js()">
</form> 

选择地区后,,单击 邮编表单,触发一个函数,获取县的值,再根据县去查询数据库对应的邮编,


函数应该怎么写?

[cpp2017]

function $(id)
{
return document.getElementById(id);
}
function js()
{
var v1 = $("TopClassID").value;
var v2 = $("BigClassID").vlaue;
var v3 = $("SmallClassID").vlaue;
var zipcode = //然后根据v1,v2,v3用ajax去查询

alert(zipcode);

}

[郭大侠_]

你这叫三级联动,不能每次都查询数据库,这样的话效率会很低.只能在页面加载时将数据一次性载入,然后用js实现联动效果,你可以参考下我在网上找的一个例子http://www.cnblogs.com/guodaxia/archive/2009/05/29/1491693.html

[lzp4881]

用不着这样，你可以直接把邮编放到县下拉框里面在，在构造
县
<select name="SmallClassID" id="SmallClassID" >
<option selected value="">西湖区</option>
</select>
的时候就把邮编查询出来，放到里面，选择后显示出来就行了，象这样
县
<select name="SmallClassID" id="SmallClassID" onchange="document.getElementById('postCode').value=this.options[this.selectedIndex].postCode;" >
<option selected value="" postCode="123456">西湖区</option>
<option selected value="" postCode="234567">xxx区</option>
...
</select>

邮编:
<input type="text" name="postCode" id="postCode">

[linsl]

是三级联动查询省市县，代码我去掉了，现在的问题是想根据县查　邮编

[linsl]

  <!--#include file="conn.asp" -->

<% 
sql = "select * from Bs_ProductClass where ClassType=2 order by ClassID asc" 
set rs = conn.execute(sql) 
%> 
<script language = "JavaScript"> 
　var onecount; 
　onecount=0; 
　subcat = new Array(); 
<% 
count1 = 0 
do while not rs.eof 
%> 
subcat[<%=count1%>] = new Array("<%= trim(rs("ClassName"))%>","<%= trim(rs("ParentClassID"))%>","<%= trim(rs("ClassID"))%>"); 
<% 
count1 = count1 + 1 
rs.movenext 
loop 
rs.close 
set rs=nothing 
%> 
onecount=<%=count1%>; 

function changelocation(ClassID1) 
{ 
　　document.myform.BigClassID.length = 0; 
　　var ClassID1=ClassID1; 
　　var i; 
　　var op1 = document.createElement("OPTION");
　　document.myform.BigClassID.options[0] = new Option('==所属大类名称==',' '); 
　　for (i=0;i < onecount; i++) 
　　{ 
　　　　if (subcat[i][1] == ClassID1) 
　　　　{ 
　　　　　　op1= new Option(subcat[i][0], subcat[i][2]); 
　　　　　　document.myform.BigClassID.options.add(op1);
　　　　} 
　　} 

} 
</script> 


<%sql2 = "select * from Bs_ProductClass where ClassType=3 order by ClassID asc" 
set rs2 = conn.execute(sql2) 
%> 
<script language = "JavaScript"> 
var onecount2; 
onecount2=0; 
subcat2 = new Array(); 
<% 
count2 = 0 
do while not rs2.eof 
%> 
subcat2[<%=count2%>] = new Array("<%= trim(rs2("ClassName"))%>","<%= trim(rs2("ParentClassID"))%>","<%= trim(rs2("ClassID"))%>","<%= trim(rs2("postcode"))%>"); 
<% 
count2 = count2 + 1 
rs2.movenext 
loop 
rs2.close 
set rs2=nothing 
%> 
onecount2=<%=count2%>; 

function changelocation2(ClassID2) 
{ 
　　document.myform.SmallClassID.length = 0; 

　　var ClassID2=ClassID2; 
　　var j; 
　　var op2 = document.createElement("OPTION");
　　document.myform.SmallClassID.options[0] = new Option('==所属小类名称==',' '); 
　　for (j=0;j < onecount2; j++) 
　　{ 
　　　　if (subcat2[j][1] == ClassID2) 
　　　　{ 
　　　　　　op2 = new Option(subcat2[j][0], subcat2[j][2]); 
               document.myform.SmallClassID.options.add(op2);

　　　　} 
　　} 

} 


</script>

调用代码

<form name='myform'>

<select name="TopClassID" id="TopClassID" onChange="changelocation(document.myform.TopClassID.options.value)" size="1"> 
<option selected value="">请选择省</option> 
<% 

sql1 = "select * from Bs_ProductClass where ClassType=1 order by ClassID asc" 
set rs1 = conn.Execute (sql1) 
do while not rs1.eof 
%> 
<option value="<%=trim(rs1("ClassID"))%>"><%=trim(rs1("ClassName"))%></option> 

<% 
rs1.movenext 
loop 
rs1.close 
set rs1 = nothing 
conn.Close 
set conn = nothing 
%> 
</select>
市
<select name="BigClassID" id="BigClassID" onChange="changelocation2(document.myform.BigClassID.options[this.options.selectedIndex].value)"> 
<option selected value="">==所有市==</option> 
</select>
县
<select name="SmallClassID" id="SmallClassID" onchange="document.getElementById('postCode').value=this.options[this.selectedIndex].postCode;" > 


<option selected value="">==所有县==</option> 
</select> 

邮编:
<input type="text"  name="postCode" id="postCode">
</form> 

to:lzp4881
按照你的方法，，我怎么把postcode数据放到option里去，因为option是读数组的