动态创建DropDownList并实现互动和跳转的web用户控件
以下代码主要供参考：怎样动态创建控件，并怎样添加控件的事件以及获得动态创建的控件的值。不足之处还请大家指出！
=================typeUc.ascx 代码部分======================
<%@ Control Language="C#" AutoEventWireup="true" CodeFile="typeUC.ascx.cs" Inherits="include_typeUC"%>
<script language="javascript" type="text/javascript">
</script>
<table width="100%" border="0" cellspacing="0" cellpadding="4" id="TABLE1" runat="server">
<tr>
<td id="TD1" runat="server">
<asp:DropDownList ID="lstProvince" runat="server" AutoPostBack="True" OnSelectedIndexChanged="lstProvince_SelectedIndexChanged" Width="70px">
<asp:ListItem Value="0">请选择</asp:ListItem>
<asp:ListItem Value="1">广东</asp:ListItem>
<asp:ListItem Value="2">北京</asp:ListItem>
<asp:ListItem Value="3">浙江</asp:ListItem>
<asp:ListItem Value="4">上海</asp:ListItem>
<asp:ListItem Value="5">香港</asp:ListItem>
<asp:ListItem Value="6">天津</asp:ListItem>
<asp:ListItem Value="7">江苏</asp:ListItem>
<asp:ListItem Value="8">重庆</asp:ListItem>
<asp:ListItem Value="9">河北</asp:ListItem>
<asp:ListItem Value="10">福建</asp:ListItem>
<asp:ListItem Value="11">辽宁</asp:ListItem>
<asp:ListItem Value="12">黑龙江</asp:ListItem>
</asp:DropDownList>
<input type="submit" name="Submit" value="确定" id="Submit1" runat="server" onserverclick="Submit1_ServerClick"/></td>
</tr>
</table>
===================typeUc.ascx.cs 代码部分======================
using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class include_typeUC : System.Web.UI.UserControl
{
protected void Page_Load(object sender, EventArgs e)
{
//Response.Write("totalDListNum:"+totalDListNum+"<br>"); //测试时使用
}
#region Web 窗体设计器生成的代码
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);
this.initA();
}
/// <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.lstProvince.SelectedIndexChanged += new System.EventHandler(this.lstProvince_SelectedIndexChanged);
this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
//创建数据库连接
SqlConnection conn = DBconn.CreateConn();
DataSet DS;//多级互动下拉列表框的数据源
SqlDataAdapter sda;
int totalDListNum;//储存应该动态创建的DropDownList的数目
public void initA()
{
//计算应该动态创建的DropDownList级数
string sql = "select max(l_ord) from types";
SqlCommand cmd = new SqlCommand(sql, conn);
conn.Open();
totalDListNum = (int)cmd.ExecuteScalar();
conn.Close();
//开始创建并绑定数据
DS = new DataSet();
sda = new SqlDataAdapter();
for (int i = 1; i <= totalDListNum; i++)
{
sda.SelectCommand = new SqlCommand("select id,name,p_id,l_ord,v1,v2,v3,v4,v5,v6,v7,v8,v9,v10,v11,v12 from types where l_ord=" + i+" or l_ord="+(i+1), conn);
sda.Fill(DS, "type" + i);
DropDownList DD = new DropDownList();
if (i < totalDListNum)
{
DD.AutoPostBack = true;
}
DD.ID = "type"+i;
DD.DataSource = DS.Tables["type" + i];
DD.DataTextField = "name";
DD.DataValueField = "id";
DD.DataBind();
DD.Items.Clear();
DD.SelectedIndexChanged += new EventHandler(this.DD_SelectedIndexChanged);
DD.Items.Add(new ListItem("-请选择-","-1"));
this.TD1.Controls.AddAt(i+1,DD);
}
}
protected void DD_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList iDD=(DropDownList)sender;
EventArgs arg=(EventArgs)e;
for (int i = 1; i < totalDListNum; i++)
{
if (iDD.ID == "type" + i)
{
DropDownList iiDD = (DropDownList)this.TD1.FindControl("type" + (i + 1));
if (Convert.ToInt32(iDD.SelectedValue) > -1)
{
DS.Tables["type" + (i + 1)].DefaultView.RowFilter = "p_id=" + iDD.SelectedValue;
iiDD.DataBind();
iiDD.Items.Insert(0, new ListItem("-请选择-", "-1"));
}
else
{
iiDD.Items.Clear();
iiDD.Items.Add(new ListItem("-请选择-","-1"));
}
for (int j = i; j < (totalDListNum-1); j++)
{
//Response.Write("j"+j+"<br>"); //测试时使用
DropDownList iiiDD = (DropDownList)this.TD1.FindControl("type" + (j+2));
iiiDD.Items.Clear();
iiiDD.Items.Add(new ListItem("-请选择-","-1"));
}
}
}
}
protected void lstProvince_SelectedIndexChanged(object sender, EventArgs e)
{
//Response.Write(this.lstProvince.SelectedValue); //测试时使用
if (this.lstProvince.SelectedValue != "0")
{
DropDownList iDD = (DropDownList)this.TD1.FindControl("type1");
DS.Tables["type1"].DefaultView.RowFilter = "p_id=0 and v" + this.lstProvince.SelectedValue + ">0";
iDD.DataBind();
for (int i = 1; i <= totalDListNum; i++)
{
DropDownList iiDD = (DropDownList)this.TD1.FindControl("type" + (i + 1));
if (iiDD != null)
{
iiDD.Items.Clear();
iiDD.Items.Add(new ListItem("-请选择-", "-1"));
}
}
iDD.Items.Insert(0, new ListItem("-请选择-", "-1"));
}
else
{
for (int i = 1; i <= totalDListNum; i++)
{
DropDownList iDD = (DropDownList)this.TD1.FindControl("type" + i);
if (iDD != null)
{
iDD.Items.Clear();
iDD.Items.Add(new ListItem("-请选择-", "-1"));
}
}
}
}
protected void Submit1_ServerClick(object sender, EventArgs e)
{
Response.Redirect("csdata/auto/index.aspx?id="+GetUrl());
}
private string GetUrl()
{
string path = "172";
for (int i = 2; i <= totalDListNum; i++)
{
DropDownList iDD = (DropDownList)this.TD1.FindControl("type" + i);
if (iDD.SelectedValue == "-1")
{
i = totalDListNum; //跳出循环
}
else
{
//path = path +","+ iDD.SelectedValue;
path = iDD.SelectedValue;
}
}
return path;
}
}
