treeview实例

aspx页面：

View Code 
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="TreeView.aspx.cs" Inherits="TreeView" %>

<!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:TreeView ID ="treeVType" runat ="server">
        </asp:TreeView>
    </div>
    </form>
</body>
</html>

aspx.cs代码：

View Code 
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using DBHelper;

public partial class TreeView : System.Web.UI.Page
{
    public static readonly string ConnectionString= ConfigurationManager.AppSettings["pubsConnectionString"].ToString();
    protected void Page_Load(object sender, EventArgs e)
    {   
        if(!IsPostBack){
           DataSet ds=new DataSet();
            ds=SqlHelper.ExecuteDataSet(ConnectionString, CommandType.StoredProcedure, "proc_getallou", null);
            dt=ds.Tables[0];
            TreeViewLoad(dt);//
        }
    }
    public void TreeViewLoad(DataTable dataSource)
    {
        if (dataSource == null)
            return;
        
        DataView athreads = null;
        athreads = new DataView(dataSource);
        athreads.RowFilter = "parentid =''";//过滤父节点ID空的节点 即为根节点
        foreach (DataRowView row in athreads)
        {
            TreeNode threadNode = new TreeNode();
            
            threadNode.Text = stringformat(HttpUtility.HtmlEncode(row["nodename"].ToString()), 30);//截取长度
            if (GetStrlength(HttpUtility.HtmlEncode(row["nodename"].ToString())) > 30)//截取长度
            {
                threadNode.ToolTip = HttpUtility.HtmlEncode(row["nodename"].ToString());
            }
            threadNode.Value = row["nodeid"].ToString();
            threadNode.Expand();//展开节点
            treeVType.Nodes.Add(threadNode);//往树添加根节点
            AddChilds(dataSource, threadNode);//调用循环添加节点方法
        }

    }
    protected void AddChilds(DataTable dt, TreeNode node)
    {

        DataView replies = new DataView(dt);
        replies.RowFilter = "parentid='" + node.Value + "'";//过滤父节点ID
        foreach (DataRowView row in replies)
        {
            TreeNode replyNode = new TreeNode();

            replyNode.Text = stringformat(HttpUtility.HtmlEncode(row["nodename"].ToString()), 30);//截取长度
            if (GetStrlength(HttpUtility.HtmlEncode(row["nodename"].ToString())) > 30)//截取长度
            {
                replyNode.ToolTip = HttpUtility.HtmlEncode(row["nodename"].ToString());
            }

            replyNode.Value = row["nodeid"].ToString();
            replyNode.Expand();
            node.ChildNodes.Add(replyNode);
            AddChilds(dt, replyNode);//调用循环添加节点方法
        }
    }
    private int GetStrlength(string str)
    {
        int t = 0;
        char[] q = str.ToCharArray();
        for (int i = 0; i < q.Length; i++)
        {
            if ((int)q[i] >= 0x4E00 && (int)q[i] <= 0x9FA5)//是否汉字
            {
                t += 2;
            }
            else
            {
                t++;
            }
        }
        return t;
    }
    private string stringformat(string str, int n)
    {
        ///
        ///格式化字符串长度，超出部分显示省略号,区分汉字跟字母。汉字2个字节，字母数字一个字节
        ///
        string temp = string.Empty;
        if (System.Text.Encoding.Default.GetByteCount(str) <= n)//如果长度比需要的长度n小,返回原字符串
        {
            return str;
        }
        else
        {
            int t = 0;
            char[] q = str.ToCharArray();
            for (int i = 0; i < q.Length && t < n; i++)
            {
                if ((int)q[i] >= 0x4E00 && (int)q[i] <= 0x9FA5)//是否汉字
                {
                    temp += q[i];
                    t += 2;
                }
                else
                {
                    temp += q[i];
                    t++;
                }
            }
            return (temp + "...");
        }

    }
}

 

posted @ 2012-04-28 15:42  zhangchun  阅读(495)  评论(0)  编辑  收藏  举报