因项目需要,要做一个菜单无限级分类,最后选择使用DroopDownList控件.时间紧急,只贴出代码,有相同需求的,可以看看
(1)数据库表说明:
PKID:不用说了吧
ClassName:类别名称
UPID:上级类别的ID(默认为0,表示一级大类)
(2)代码如下:
<1>default.aspx页面代码如下:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:PlaceHolder ID="PH" runat="server"></asp:PlaceHolder>
<asp:Button ID="btn_Enter" runat="server" OnClick="btn_Enter_Click" Text=" 确定 " /></div>
</form>
</body>
</html>
<2>default.aspx.cs代码如下:
using System;
using System.Data;
using System.Configuration;
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;
using System.Collections;
using System.Data.SqlClient;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
ArrayList al;
if (Session["Controls"] != null)
{
al = (ArrayList)Session["Controls"];
PH.Controls.Clear();
for (int i = 0; i < al.Count; i++)
{
DropDownList ddl = (DropDownList)al[i];
ddl.SelectedIndexChanged += new EventHandler(dl_SelectedIndexChanged);
PH.Controls.Add(ddl);
}
}
if (!IsPostBack)
{
CreateControls("select * from t_sj_classinfo where upid=0", 0);
}
}
void CreateControls(string sql, int CurID)
{
ArrayList al;
if (Session["Controls"] == null)
al = new ArrayList();
else
{
al = (ArrayList)Session["Controls"];
for (int i = 0; i < al.Count; i++)
{
DropDownList ddl_Remove = (DropDownList)al[i];
if (Convert.ToInt32(ddl_Remove.ID) > CurID)
{
i--;
al.Remove(ddl_Remove);
PH.Controls.Remove(ddl_Remove);
}
}
}
SqlConnection conn = new SqlConnection("server=localhost;uid=sa;pwd=123456;database=test");
SqlCommand cmd = new SqlCommand(sql, conn);
DataTable dt = new DataTable();
SqlDataAdapter drp = new SqlDataAdapter(cmd);
drp.Fill(dt);
if (dt.Rows.Count > 0)
{
DropDownList dl = new DropDownList();
CurID++;
dl.ID = CurID.ToString();
dl.AutoPostBack = true;
dl.SelectedIndexChanged += new EventHandler(dl_SelectedIndexChanged);
dl.DataSource = dt;
dl.DataTextField = "ClassName";
dl.DataValueField = "PKID";
dl.DataBind();
dl.Items.Insert(0, new ListItem("--请选择--", "0"));
al.Add(dl);
PH.Controls.Add(dl);
Session["Controls"] = al;
}
}
void dl_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList dl = (DropDownList)sender;
string LBID = dl.SelectedValue;
CreateControls("select * from t_sj_classinfo where upid=" + LBID, Convert.ToInt32(dl.ID));
}
protected void btn_Enter_Click(object sender, EventArgs e)
{
ControlCollection Ctl = PH.Controls;
System.Text.StringBuilder sb = new System.Text.StringBuilder();
foreach (Control c in Ctl)
{
//如果PH中还有其它的服务器控件,此处必须加入服务器控件类型的判断
DropDownList dl = (DropDownList)c;
sb.Append("选中的文本：" + dl.SelectedItem.Text + " 选中的值：" + dl.SelectedItem.Value + "<br/>");
}
Response.Write(sb.ToString());
}
}
最后显示的结果页面样例如:
