Default.aspx
<%@ 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>无标题页</title> </head> <body> <form id="form1" runat="server"> <div> <asp:PlaceHolder ID="PlaceHolder1" runat="server"></asp:PlaceHolder> <br /> <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" /></div> </form> </body> </html>
Default.aspx.cs
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 Model; using BLL; public partial class _Default : System.Web.UI.Page { private CategoryBLL _categoryBLL = new CategoryBLL(); private Category _category = new Category(); private void Page_Init(object sender, System.EventArgs e) { BindDrpClass(); } protected void Page_Load(object sender, EventArgs e) { string str = "8/14/19/25"; //数据库读取 string[] arr = str.Split('/'); if (arr.Length == PlaceHolder1.Controls.Count) //防止新增类别时读取出错 { for (int i = 0; i < PlaceHolder1.Controls.Count; i++) { if (PlaceHolder1.Controls[i] is DropDownList) { ((DropDownList)PlaceHolder1.Controls[i]).SelectedValue = arr[i]; } } } } private void BindDrpClass() { DataTable dt = _categoryBLL.GetCategory(); DataRow[] drs = dt.Select("pid=0"); foreach (DataRow dr in drs) { string id = dr["id"].ToString(); string name = dr["name"].ToString(); DropDownList ddl = new DropDownList(); ddl.Items.Clear(); ddl.ID = "ddl" + id; ddl.Items.Add(new ListItem("－" + name + "－", id)); PlaceHolder1.Controls.Add(ddl); int sonparentid = int.Parse(id); BindDrpNode(sonparentid, dt, ddl); } } private void BindDrpNode(int parentid, DataTable dt, DropDownList ddl) { DataRow[] drs = dt.Select("pid= " + parentid); foreach (DataRow dr in drs) { string id = dr["id"].ToString(); string name = dr["name"].ToString(); ddl.Items.Add(new ListItem(name, id)); PlaceHolder1.Controls.Add(ddl); } } protected void Button1_Click(object sender, EventArgs e) { string category = ""; string category2 = ""; foreach (Control childControl in PlaceHolder1.Controls) { if (childControl is DropDownList) { category += "/" + ((DropDownList)childControl).SelectedItem.Text; category2 += "/" + ((DropDownList)childControl).SelectedValue; } } if (category.Length > 0) category = category.Remove(0, 1); Response.Write(category); Response.Write("<br />"); if (category2.Length > 0) category2 = category2.Remove(0, 1); Response.Write(category2); } }