利用.net 2.0中的TreeView控件与数据库绑定,生成无限级的树目录
数据表的结构
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.Data.SqlClient;
public partial class _Default : System.Web.UI.Page
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{
protected string _connstr = ConfigurationManager.ConnectionStrings["DemoConnectionstrings"].ConnectionString;
protected void Page_Load(object sender, EventArgs e)
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{
if (!Page.IsPostBack)
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{
BindTree();
using (SqlConnection _conn = new SqlConnection(_connstr))
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{
SqlCommand _comm = new SqlCommand("select * from treeview", _conn);
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_conn.Open();
using (SqlDataReader r = _comm.ExecuteReader())
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{
while (r.Read())
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{
ListItem item = new ListItem(r["txt"].ToString(), r["id"].ToString());
this._dd_parent.Items.Add(item);
}
}
}
this._dd_parent.Items.Insert(0, new ListItem("![](https://www.cnblogs.com/Images/dot.gif)
.", "0"));
}
}
protected void BindTree()
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{
TreeNode node = new TreeNode(); //这里是创建一个根节点,就是dome中看到的Root
node.Text = "Root";
CreateChildTree(node, 0);
_tree_view.Nodes.Add(node);
}
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protected void CreateChildTree(TreeNode _parentNode, int _parentID)
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{
using (SqlConnection _conn = new SqlConnection(_connstr))
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{
SqlCommand _comm = new SqlCommand();
string sql = "select * from treeview where rootid=@rootid";
_comm.Parameters.Add("@rootid", SqlDbType.Int).Value = _parentID;
_comm.CommandText = sql;
_comm.Connection = _conn;
_conn.Open();
using (SqlDataReader r = _comm.ExecuteReader())
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{
while (r.Read())
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{
TreeNode _node = new TreeNode(r["txt"].ToString());
CreateChildTree(_node, (int)r["ID"]); //递归出子节点
_parentNode.ChildNodes.Add(_node);
}
}
}
}
protected void _btn_submit_Click(object sender, EventArgs e)
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{
int _rootid = Convert.ToInt16(this._dd_parent.SelectedValue);
string _txt = this._txt_txt.Text.Trim();
using (SqlConnection _conn = new SqlConnection(_connstr))
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{
SqlCommand _comm = new SqlCommand("insert into treeview (txt,rootid) values (@txt,@id)", _conn);
_comm.Parameters.Add("@txt", SqlDbType.VarChar, 50).Value = _txt;
_comm.Parameters.Add("@id", SqlDbType.Int).Value = _rootid;
_conn.Open();
_comm.ExecuteNonQuery();
}
this._tree_view.Nodes.Clear();
BindTree();
}
}
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原文地址:https://www.cnblogs.com/xiang/p/449944.html