ASP.net DropDownList 无刷新联动！
<TITLE>WebForm2</TITLE>
<SCRIPT language='javascript'>
function load(){
var drp2 = document.getElementById("DropDownList2");
drp2.innerText="";
for(var i = 0;i<=drp2.options.length -1;i++){
drp2.remove(i);
}
var drp3 = document.getElementById("DropDownList3");
for(var i = 0;i<=drp3.options.length -1;i++){
drp3.remove(i);
}
var xmlhttp = new ActiveXObject("MSXML2.XMLHTTP");
var oDoc = new ActiveXObject("MSXML2.DOMDocument");
var state=document.getElementById("DropDownList1").value;
xmlhttp.open("POST", "webform1.aspx?id="+state,false);
xmlhttp.send("");
var res=oDoc.loadXML(xmlhttp.responseText);
var naItems = oDoc.selectNodes("//Market/Table/maName");
var idItems = oDoc.selectNodes("//Market/Table/maId");
var item;
var id;
for (item = naItems.nextNode(),id=idItems.nextNode(); item&&id; item = naItems.nextNode(),id=idItems.nextNode()){
var nastr = item.nodeTypedValue;
var idstr = id.nodeTypedValue;
var newOption = document.createElement("OPTION");
newOption.text =nastr;
newOption.value = idstr;
drp2.options.add(newOption);
}
load2();
}
function load2(){
var drp2 = document.getElementById("DropDownList3");
drp2.innerText="";
for(var i = 0;i<=drp2.options.length -1;i++){
drp2.remove(i);
}
var xmlhttp = new ActiveXObject("MSXML2.XMLHTTP");
var oDoc = new ActiveXObject("MSXML2.DOMDocument");
var state=document.getElementById("DropDownList2").value;
xmlhttp.open("POST", "webform3.aspx?id="+state,false);
xmlhttp.send("");
var res=oDoc.loadXML(xmlhttp.responseText);
var naItems = oDoc.selectNodes("//Market/Table/maName");
var idItems = oDoc.selectNodes("//Market/Table/maId");
var item;
var id;
for (item = naItems.nextNode(),id=idItems.nextNode(); item&&id; item = naItems.nextNode(),id=idItems.nextNode()){
var nastr = item.nodeTypedValue;
var idstr = id.nodeTypedValue;
var newOption = document.createElement("OPTION");
newOption.text =nastr;
newOption.value = idstr;
drp2.options.add(newOption);
}
}
</SCRIPT>
</HEAD>
<BODY ms_positioning="GridLayout" onload="load()">
<FORM id="Form1" method="post" runat="server">
<ASP:DROPDOWNLIST id="DropDownList1" runat="server"></ASP:DROPDOWNLIST>
<ASP:DROPDOWNLIST id="DropDownList2" runat="server"></ASP:DROPDOWNLIST>
<ASP:DROPDOWNLIST id="Dropdownlist3" runat="server"></ASP:DROPDOWNLIST>
</FORM>
</BODY>
</HTML>
-----------------------
namespace dropDown
{
/// <summary>
/// WebForm2 的摘要说明。
/// </summary>
public class WebForm2 : System.Web.UI.Page
{
protected System.Web.UI.WebControls.DropDownList DropDownList1;
protected System.Web.UI.WebControls.DropDownList Dropdownlist3;
protected System.Web.UI.WebControls.DropDownList DropDownList2;
private void Page_Load(object sender, System.EventArgs e)
{
// 在此处放置用户代码以初始化页面
if(!this.IsPostBack)
{
SqlConnection con = new SqlConnection("server=localhost;database=star;uid=sa;pwd=");
SqlDataAdapter da = new SqlDataAdapter("select maId,maName from tabMarket where maCls=0",con);
DataSet ds = new DataSet();
da.Fill(ds,"op");
this.DropDownList1.DataSource=ds.Tables[0];
this.DropDownList1.DataTextField = "maName";
this.DropDownList1.DataValueField = "maId";
this.DropDownList1.DataBind();
this.DropDownList1.Attributes.Add("onchange","load()");
this.DropDownList2.Attributes.Add("onchange","load2()");
}
}
}
}
-----------------------
public class WebForm1 : System.Web.UI.Page
{
private void Page_Load(object sender, System.EventArgs e)
{
// 在此处放置用户代码以初始化页面
// Put user code to initialize the page here
//if(this.Request["state"]!=null)
//{
string id =this.Request["id"];
SqlConnection con = new SqlConnection("server=localhost;database=star;uid=sa;pwd=;");
SqlDataAdapter da = new SqlDataAdapter("select maName,maId from tabMarket where maParent=@id and maSt=1 ",con);
da.SelectCommand.Parameters.Add("@id",id);
DataSet ds = new DataSet("Market");
da.Fill(ds);
ds.WriteXml(Response.OutputStream);
Response.Flush ();
Response.End ();
//}
}
}
-----------------------------
public class WebForm3 : System.Web.UI.Page
{
private void Page_Load(object sender, System.EventArgs e)
{
// 在此处放置用户代码以初始化页面
string id =Request["id"];
SqlConnection con = new SqlConnection("server=localhost;database=star;uid=sa;pwd=;");
SqlDataAdapter da = new SqlDataAdapter("select maName,maId from tabMarket where maParent=@id and maSt=1",con);
da.SelectCommand.Parameters.Add("@id",id);
DataSet ds = new DataSet("Market");
da.Fill(ds);
ds.WriteXml(Response.OutputStream);
Response.Flush ();
Response.End ();
}
}
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