http://tb.blog.csdn.net/TrackBack.aspx?PostId=1377536
再谈 N 个 ASP.net DropDownList 无刷新联动菜单，牺牲N-1个ASPX来实现自动更新机制，避免刷新的闪动！！
以下代码绝对可以使用，也可以实现多级菜单。。。。
<script language="javascript"> function load(state) { var drp2 = document.getElementById("DropDownList2"); for(var i=0;i<=drp2.options.length-1;i++) { drp2.remove(i); } var oHttpReq = new ActiveXObject("MSXML2.XMLHTTP"); //发送请求 var oDoc = new ActiveXObject("MSXML2.DOMDocument"); //响应结果 var state=document.getElementById("DropDownList1").value; oHttpReq.open("post","webform2.aspx?state="+state, false); oHttpReq.send(""); result = oHttpReq.responseText; oDoc.loadXML(result); // items = oDoc.selectNodes("//CITY/Table"); items = oDoc.selectNodes("//address/Table"); for (var item = items.nextNode();item;item = items.nextNode()) { var city = item.selectSingleNode("//address").nodeTypedValue; var newOption = document.createElement("OPTION"); newOption.text = city; newOption.value = city; drp2.options.add(newOption); } } </script>
============================
webform1.aspx
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(!IsPostBack) { SqlConnection con = new SqlConnection("packet size=4096;user id=sa;data source=SERVER;persist security info=False;initial catalog=pubs"); SqlDataAdapter da = new SqlDataAdapter("select state from authors group by state",con); DataSet ds = new DataSet("State"); da.Fill(ds); this.DropDownList1.DataSource = ds.Tables[0]; this.DropDownList1.DataTextField = "state"; this.DropDownList1.DataValueField = "state"; this.DropDownList1.DataBind(); this.DropDownList1.Attributes.Add("onchange","load()"); //DropDownList1. } }
webform2.aspx
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.Request["state"]!=null) { string state = this.Request["state"].ToString(); SqlConnection con = new SqlConnection("packet size=4096;user id=sa;data source=SERVER;persist security info=False;initial catalog=pubs"); SqlDataAdapter da = new SqlDataAdapter("select address from authors where state = '"+state+"'",con); DataSet ds = new DataSet("address"); da.Fill(ds); XmlTextWriter writer = new XmlTextWriter(Response.OutputStream, Response.ContentEncoding); writer.Formatting = Formatting.Indented; writer.Indentation = 4; writer.IndentChar = ' '; ds.WriteXml(writer); writer.Flush(); Response.End(); writer.Close(); } }
---------------------------------
仔细看看``其实完全不用在响应多个DROPLIST的时候牺牲 N-1 个页面，因为所有的响应都有一个共性，为什么不可以多传一个值进行判断响应那一个方法呢？？？
var type ="type1";
oHttpReq.open("post","webform2.aspx?state="+state+"&type="+type, false);
string type = this.Request["type"].ToString();
switch(type)
{
case "type1":
.........................................
}
----------------------------------------------
程序需要做几处修改：
1、解决drp2、drp3清楚不完全的问题： drp2.innerText =""; drp3.......................
2、
for (var item = items.nextNode();item;item = items.nextNode()) { var city = item.nodeTypedValue; var newOption = document.createElement("OPTION"); newOption.text = city; newOption.value = city; drp2.options.add(newOption); } 3、如果传多个值的问题也是一样``
select t1,t2 from tt
只要多加一个条件就可以解决问题
=======================================================
这个还有很多可以研究的问题``比如刷新后值的问题。。。。。。。。。。。。
Trackback: http://tb.blog.csdn.net/TrackBack.aspx?PostId=548121
程序演示地址：http://www.718.com.cn/other/Example.aspx
在网上看到了一些无刷新的联动控件。下下了测试以后，显示英文和数字可以，但是不可以显示中文，后来把从网上down下来的文件做了一个翻修改，做了一个省市的联动控件。给大家共享一下。可以显示中文了。
<%@ Page language="c#" Codebehind="Example.aspx.cs" AutoEventWireup="false" Inherits="Webs.other.Example" %> <HTML> <HEAD> <title>Example</title> <meta name="GENERATOR" Content="Microsoft Visual Studio .NET 7.1"> <meta name="CODE_LANGUAGE" Content="C#"> <meta name="vs_defaultClientScript" content="JavaScript"> <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5"> <script> function load(state){ var drp2 = document.getElementById("DropDownList2"); for (i = drp2.length; i >= 0; i--){ drp2.options.remove(i); } var oHttpReq = new ActiveXObject("MSXML2.XMLHTTP"); var oDoc = new ActiveXObject("MSXML2.DOMDocument"); oHttpReq.open("POST", "getData.aspx?state="+state, false); oHttpReq.send(""); result = oHttpReq.responseText; oDoc.loadXML(result); items1 = oDoc.selectNodes("//CITY/Table/Id"); items2 = oDoc.selectNodes("//CITY/Table/shiname"); var itemsLength=items1.length; for(i=0;i<itemsLength;i++) //将小类的类名和编号赋予DropDownList2 { var newOption = document.createElement("OPTION"); newOption.text=items2[i].text; newOption.value=items1[i].text; drp2.options.add(newOption); } } window.onload = function(){load('1');} </script> </HEAD> <body MS_POSITIONING="FlowLayout"> <form id="Form1" method="post" runat="server"> <asp:DropDownList id="DropDownList1" runat="server"></asp:DropDownList> <asp:DropDownList id="DropDownList2" runat="server"></asp:DropDownList> <asp:TextBox id="TH" runat="server"></asp:TextBox> <asp:Button id="Button1" runat="server" Text="Button"></asp:Button> </form> </body> </HTML>
cs源文件:
using System; using System.Collections; using System.ComponentModel; using System.Data; using System.Drawing; using System.Web; using System.Web.SessionState; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls; using System.Data.SqlClient;
namespace Webs.other { /// <summary> /// Example 的摘要说明。 /// </summary> public class Example : System.Web.UI.Page { protected System.Web.UI.WebControls.DropDownList DropDownList1; protected System.Web.UI.WebControls.TextBox TH; protected System.Web.UI.WebControls.Button Button1; 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) { // 建立数据源加载第一个DropDownList，也可以默认加载第二个 SqlConnection con = new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings.Get("connStr1")); SqlDataAdapter da = new SqlDataAdapter("select Id,shengname from Province",con); DataSet ds = new DataSet(); da.Fill(ds); this.DropDownList1.DataSource = ds; this.DropDownList1.DataTextField = "shengname"; this.DropDownList1.DataValueField = "Id"; this.DropDownList1.DataBind(); // 这里是绑定客户端事件，当第一个DropDownList的选项改变时激发下面的事件onchange，这个事件将调用一个客户端方法load() this.DropDownList1.Attributes.Add("onchange","load(this.options[this.selectedIndex].value)"); } }
#region Web Form Designer generated code override protected void OnInit(EventArgs e) { // // CODEGEN：该调用是 ASP.NET Web 窗体设计器所必需的。 // InitializeComponent(); base.OnInit(e); } /// <summary> /// 设计器支持所需的方法 - 不要使用代码编辑器修改 /// 此方法的内容。 /// </summary> private void InitializeComponent() { this.Button1.Click += new System.EventHandler(this.Button1_Click); this.Load += new System.EventHandler(this.Page_Load);
} #endregion
private void Button1_Click(object sender, System.EventArgs e) { TH.Text=this.Request.Form["DropDownList2"].ToString(); } } }
getdata源文件
using System; using System.Collections; using System.ComponentModel; using System.Data; using System.Drawing; using System.Web; using System.Web.SessionState; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls; using System.Data.SqlClient; using System.Xml; using System.Configuration; using System.Text;
namespace Webs.other { /// <summary> /// GetData 的摘要说明。 /// </summary> public class GetData : 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 //Response.Write(Request["state"]); int shengNo=int.Parse(Request["state"].ToString()); SqlConnection con = new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings.Get("connStr1")); SqlDataAdapter da = new SqlDataAdapter("select Id,shiname from City where Shengid='"+shengNo+"'",con); DataSet ds = new DataSet("CITY"); da.Fill(ds);
XmlTextWriter writer = new XmlTextWriter(Response.OutputStream,Encoding.UTF8); writer.Formatting = Formatting.Indented; writer.Indentation = 4; writer.IndentChar = ' '; writer.WriteStartDocument(); ds.WriteXml(writer); writer.Flush(); Response.End(); writer.Close(); }
#region Web Form Designer generated code override protected void OnInit(EventArgs e) { // // CODEGEN：该调用是 ASP.NET Web 窗体设计器所必需的。 // InitializeComponent(); base.OnInit(e); } /// <summary> /// 设计器支持所需的方法 - 不要使用代码编辑器修改 /// 此方法的内容。 /// </summary> private void InitializeComponent() { this.Load += new System.EventHandler(this.Page_Load); } #endregion } }
Trackback: http://tb.blog.csdn.net/TrackBack.aspx?PostId=472917
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" οnlοad="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 (); } } ------------------
