TreeView绑定数据库数据

TreeView控件可以通过递归方式绑定数据库数据，代码如下：

    void Page_Load()
    {
        if (!Page.IsPostBack)
            PopulateTreeView();
    }

    private void PopulateTreeView()
    {
        DataTable treeViewData = GetTreeViewData();
        AddTopTreeViewNodes(treeViewData);  //绑定父节点
    }

    private DataTable GetTreeViewData()    //获取数据
    {
        string selectCommand = "SELECT MessageId,ParentId,Subject FROM Discuss";
        string conString = WebConfigurationManager.ConnectionStrings["Discuss"].ConnectionString;
        SqlDataAdapter dad = new SqlDataAdapter(selectCommand, conString);
        DataTable dtblDiscuss = new DataTable();
        dad.Fill(dtblDiscuss);
        return dtblDiscuss;
    }

    private void AddTopTreeViewNodes(DataTable treeViewData)
    {
        DataView view = new DataView(treeViewData);
        view.RowFilter = "ParentID IS NULL";
        foreach (DataRowView row in view)
        {
            TreeNode newNode = new TreeNode(row["Subject"].ToString(), row["MessageId"].ToString());
            TreeView1.Nodes.Add(newNode);
            AddChildTreeViewNodes(treeViewData, newNode);//绑定子节点
        }

    }

    private void AddChildTreeViewNodes(DataTable treeViewData, TreeNode parentTreeViewNode)
    {
        DataView view = new DataView(treeViewData);
        view.RowFilter = "ParentID=" + parentTreeViewNode.Value;
        foreach (DataRowView row in view)
        {
            TreeNode newNode = new TreeNode(row["Subject"].ToString(), row["MessageId"].ToString());
            parentTreeViewNode.ChildNodes.Add(newNode);
            AddChildTreeViewNodes(treeViewData, newNode);//递归，绑定子节点
        }
    }

数据表中记录通过ParentId字段指定父节点。

详细介绍可以参考：《ASP.NET2.0揭秘卷1》

 树节点TreeNode的重要属性：

Text：节点显示内容

Value：节点对应值

NavigateUrl：导航页面Url

Target：目标框架

ImageUrl：节点图像