asp:DropDownList 绑定数据库的问题 100分啊

Question

置顶bigclass的AutoPostBack为true
在bigclass的SelectedIndexChanged事件里面重新读取数据库smallcalss
并且绑定到smallclass

Answer 1

bigclass_SelectedIndexChanged(object sender System.Evnet... e)
{
    DataTable dt = GetYourSmallClassByBigClassId(this.bigclass.SelectedValue);
    this.smallclass.DataSource = dt;
    this.smallclass.DataTextField = ...
    ...............
    this.smallclass.DataBind();
}

Answer 2

不要忘了设置你的bigclass的AutoPostBack为true

Answer 3

呵呵，最简单的就是
brightheroes(闭关|那一剑的风情) 
如果，你想做好一点，不刷新页面，可以在客户端加载XML文件。

Answer 4

看看这个，只是个思路，我自已用的，是三级联动不刷新的例子<script language="javascript"> function area_change(v)
{
   v=document.all.to_area.options[document.all.to_area.selectedIndex].value;
myform.to_city.length=0;
var o=new Option('到达城市','-1');
myform.to_city.add(o);
myform.to_country.length=0;
myform.to_country.disabled=true;
var o=new Option('载入中...','-1');
myform.to_country.add(o);
dataprocess.src="dataprocess.aspx?mode=area_country&upid="+v;
myform.to_country.disabled=false;
}

function country_change(v)
{

            v=document.all.to_country.options[document.all.to_country.selectedIndex].value;
myform.to_city.length=0;
myform.to_city.disabled=true;
var o=new Option('载入中...','0');
myform.to_city.add(o); dataprocess.src="dataprocess.aspx?mode=area_city&upid="+v;
myform.to_city.disabled=false;
}
function city_change()
{
v=document.all.to_city.options[document.all.to_city.selectedIndex].text;
document.all.city_text.value=v;
}
</script>
<script language="javascript" id="dataprocess"></script>
<script>
 <tr>
                    <td height="22" class="样式4"> <div align="center">到达大州</div></td>
                    <td height="22" class="样式4"><span class="forumRow">
                    <asp:DropDownList ID="to_area" runat="server"  OnChanged="area_change(this.value)">
                      <asp:ListItem Value="-1">到达大州</asp:ListItem>
                    </asp:DropDownList>
</span></td>
                    <td class="样式4">到达国家</td>
                    <td class="样式4"><span class="forumRow">
                      <asp:DropDownList ID="to_country" runat="server" OnChanged="country_change(this.value)" Width="95" >
                        <asp:ListItem Value="-1">到达国家</asp:ListItem>
                      </asp:DropDownList>
                    </span></td>
                    <td class="样式4"><span class="forumRow"></span></td>
                    <td class="样式4">到达城市 </td>
                    <td class="样式4"><span class="forumRow">
                      <asp:DropDownList ID="to_city"   OnChanged="city_change()"  CssClass="select" runat="server">
                        <asp:ListItem value="-1">选择到达地</asp:ListItem>
                      </asp:DropDownList>
                    </span> </td>
                  </tr>

Answer 5

dataprocess.cs
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Web.Mail;
using System.Text.RegularExpressions;
using System.Data.SqlClient;
namespace plane
{
/// <summary>
/// tree_Index μ??aòa?μ?÷?￡
/// </summary>
public class dataprocess : System.Web.UI.Page
{       
                 
        protected config conn=new config();
string str_Sql;
private void Page_Load(object sender, System.EventArgs e)
{
    if (Request.QueryString["mode"]=="area_country"){
    string area_id=Request.QueryString["upid"];
    str_Sql="select id,country_name from country where area_id="+area_id; 
conn.ExeSql1(str_Sql);
Response.Write("myform.to_country.length=0");
Response.Write(";");
Response.Write("var o=new Option('到达国家','-1')");
Response.Write(";");
        Response.Write("myform.to_country.add(o)");
Response.Write(";");
string id;
string country_name; 
while(conn.myReader.Read())
    {
 id=conn.myReader.GetValue(0).ToString().Trim();
 country_name=conn.myReader.GetValue(1).ToString().Trim();
Response.Write("var o=new Option('"+country_name+"','"+id+"')");
Response.Write(";");
Response.Write("myform.to_country.add(o)");
Response.Write(";");
}
conn.closeReader();
}
else if (Request.QueryString["mode"]=="area_city"){
        string country_id=Request.QueryString["upid"];
        str_Sql="select id,city_name from city where country_id="+country_id; 
conn.ExeSql1(str_Sql);
Response.Write("myform.to_city.length=0");
Response.Write(";");
Response.Write("var o=new Option('到达城市','-1')");
Response.Write(";");
        Response.Write("myform.to_city.add(o)");
Response.Write(";");
string id;
string city_name; 
while(conn.myReader.Read())
    {
 id=conn.myReader.GetValue(0).ToString().Trim();
 city_name=conn.myReader.GetValue(1).ToString().Trim();
Response.Write("var o=new Option('"+city_name+"','"+id+"')");
Response.Write(";");
Response.Write("myform.to_city.add(o)");
Response.Write(";");
}
conn.closeReader();
}
}
#region Web Form Designer generated code
override protected void OnInit(EventArgs e)
{
//
// CODEGEN￡o??μ÷ó?ê? ASP.NET Web ′°ì?éè???÷?ù±?Dèμ??￡
//
InitializeComponent();
base.OnInit(e);
}

/// <summary>
/// éè???÷?§3??ùDèμ?·?·¨ - 2?òaê1ó?′ú??±à?-?÷DT??
/// ′?·?·¨μ??úèY?￡
/// </summary>
private void InitializeComponent()
{    
//this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
}
}

Answer 6

天啊 代码 有没有是 vb.net的啊 

Answer 7

AutopostBack=True.(bigclass)其他的就很Easy了。

Answer 8

AutopostBack=True.(bigclass)其他的就很Easy了。

Answer 9

private void DropDownList1_SelectedIndexChanged(object sender, System.EventArgs e)
{
if(this.DropDownList1.SelectedValue!="")
{
int id = int.Parse(this.DropDownList1.SelectedValue.Trim());
DataSet ds=dm.selectall(id);
this.namebox.Text = ds.Tables[0].Rows[0][0].ToString();
this.comboBox1.SelectedValue = ds.Tables[0].Rows[0][1].ToString();
this.moneybox.Text = ds.Tables[0].Rows[0][2].ToString();
this.cmbox.Text = ds.Tables[0].Rows[0][3].ToString();
}
}

Answer 10

我在求 vb.net的 代码啊 大哥们 帮我啊