动态树状图的小问题！！！！

原来 2011-03-31 03:32:12

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="default.aspx.cs" Inherits="Test._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" method="post">
<asp:TreeView ID="treeViewOne" runat="server">

</asp:TreeView>
</form>
</body>
</html>

-------------------------------------
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 System.Data.SqlClient;

namespace Test
{
public partial class _Default : System.Web.UI.Page
{
SqlConnection con = new SqlConnection("server=.;database=mysqlserver;uid=sa;pwd=sa1234");
DataSet ds;
protected void Page_Load(object sender, EventArgs e)
{
con.Open();
this.createDataset();
con.Close();
this.initTree(treeViewOne.Nodes,"0");
}
private DataSet createDataset() {
ds = new DataSet();
string sql = "select * from category;";
SqlDataAdapter sda = new SqlDataAdapter(sql,con);
sda.Fill(ds, "category");
return ds;
}
protected void initTree(TreeNodeCollection tnc,string parentId) {//递归方法动态生成节点；
DataView dv = new DataView();
TreeNode tempNode;
dv.Table = ds.Tables["category"];
dv.RowFilter = "parentId='"+parentId+"'";
foreach(DataRowView div in dv){
tempNode = new TreeNode();
tempNode.Value = div["category"].ToString();
tempNode.Text = div["category"].ToString();
tempNode.NavigateUrl = "#";
tnc.Add(tempNode);
this.initTree(tempNode.ChildNodes,tempNode.Value);
}
}
}

}
---------------------------------------
“/”应用程序中的服务器错误。
--------------------------------------------------------------------------------

无法在 System.Int32 和 System.String 上执行“=”操作。
说明: 执行当前 Web 请求期间，出现未处理的异常。请检查堆栈跟踪信息，以了解有关该错误以及代码中导致错误的出处的详细信息。

异常详细信息: System.Data.EvaluateException: 无法在 System.Int32 和 System.String 上执行“=”操作。

源错误:

行 37: TreeNode tempNode;
行 38: dv.Table = ds.Tables["category"];
行 39: dv.RowFilter = "parentId='"+parentId+"'";
行 40: foreach(DataRowView div in dv){
行 41: tempNode = new TreeNode();

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请各位大侠看下，帮我修改下，不知道哪里错了！！感激不尽啊！！

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