treeview 递归遍历
0
悬赏园豆：50
[已解决问题]
解决于 2009-07-09 08:08
//调用的方法
private void addprtreeview()
{
SqlHelper shp = new SqlHelper();
string sqlstr = "select * from nodesTB ";
DataSet ds = new DataSet();
ds = shp.Query(sqlstr);
this.treeView1.Nodes.Clear();
TreeNode tt=new TreeNode();
LoadTree(tt,ds);
this.label1.Text = "个人心情多媒体空间站";
}
//递归方法
private void LoadTree(TreeNode tn,DataSet ds)
{
//加载根节点
if (tn == null)
{
//从数据库获取上级节点编号=0的DataSet
foreach (DataRow dr in ds.Tables[0].Rows)
{
TreeNode newtn = new TreeNode();
newtn.Text = dr["nodetext"].ToString();
newtn.Tag = dr["nodeID"].ToString().Trim();
newtn.ContextMenuStrip = this.contextMenuStrip1;
tn.Nodes.Add(newtn);
LoadTree(newtn, ds);//递归
}
}
//获取当前节点的下一层节点DataSet
else
{
foreach (DataRow dr in ds.Tables[0].Rows)
{
TreeNode newtn = new TreeNode();
newtn.Text = dr["nodetext"].ToString();
newtn.Tag = dr["nodeID"].ToString().Trim();
newtn.ContextMenuStrip = this.contextMenuStrip1;
tn.Nodes.Add(newtn);
LoadTree(newtn, ds);//递归
}
}
问题：出现了死循环。我的参考：http://zhidao.baidu.com/question/64884430.html
最佳答案
0
private void LoadTree(TreeNode tn,DataSet ds)
{
//加载根节点
if (tn == null)
{
//从数据库获取上级节点编号=0的DataSet
foreach (DataRow dr in ds.Tables[0].Rows)
{
TreeNode newtn = new TreeNode();
newtn.Text = dr["nodetext"].ToString();
newtn.Tag = dr["nodeID"].ToString().Trim();
newtn.ContextMenuStrip = this.contextMenuStrip1;
tn.Nodes.Add(newtn);
LoadTree(newtn, ds);//递归
这个地方有问题！！虽然你把新节点传进去了，但是你的数据源还是全部节点的数据源，你应该传进去的是当前新节点的 子节点 的集合！！，不然就是无休止的循环。递归－应该是越来越少的。
}
}
//获取当前节点的下一层节点DataSet
else
{
foreach (DataRow dr in ds.Tables[0].Rows)
{
TreeNode newtn = new TreeNode();
newtn.Text = dr["nodetext"].ToString();
newtn.Tag = dr["nodeID"].ToString().Trim();
newtn.ContextMenuStrip = this.contextMenuStrip1;
tn.Nodes.Add(newtn);
LoadTree(newtn, ds);//递归
同样的问题！！！！
}
}
其他回答(1)
0
private DataTable dt;
protected void Page_Load(object sender, EventArgs e)
{
dt = new MapHelp().GetAreaTreeView("0");
if (!IsPostBack)
{
TreeNode tnode = new TreeNode();
tnode.Text = "中國";
tnode.Value = "1";
tnode.ToolTip = "1";
HouseTree.Nodes.Add(tnode);//添加根節點
GetTreeData(tnode);//添加下一層節點
}
detailDiv.InnerHtml = detailHidden.Value;
}
private void GetTreeData(TreeNode node)
{
DataRow[] dr = dt.Select("up_id=1");
foreach (DataRow mydr in dr)
{
TreeNode tnode = new TreeNode();
tnode.Text = mydr["area_nm"].ToString().Trim();
tnode.Value = mydr["area_id"].ToString().Trim();
tnode.ToolTip = tnode.Value;
node.ChildNodes.Add(tnode);
//AddHouseTreeChildNodes(dt, tnode);//此句放開則加載所有節點
//tnode.Expanded = false;
}
}
private void AddHouseTreeChildNodes(DataTable dt ,TreeNode node)
{
DataRow[] dr = dt.Select("up_id=" + node.Value);
foreach (DataRow mydr in dr)
{
TreeNode childNode = new TreeNode();
childNode.Text = mydr["area_nm"].ToString().Trim();
childNode.Value = mydr["area_id"].ToString().Trim();
node.ChildNodes.Add(childNode);
AddHouseTreeChildNodes(dt, childNode);
}
}
protected void HouseTree_SelectedNodeChanged(object sender, EventArgs e)
{
detailDiv.InnerHtml = "";
HouseTree.SelectedNode.ChildNodes.Clear();//清空節點以免重複添加節點
AddHouseTreeChildNodes(dt, HouseTree.SelectedNode);
DataTable mydt = new MapHelp().GetHouseInformation(HouseTree.SelectedNode.Value);
if (dt != null && dt.Rows.Count > 0)
{
AddTreeFileData(mydt, HouseTree.SelectedNode);
HouseTree.SelectedNode.Expanded = true;
}
//明細資料顯示
DataTable detailTab = new MapHelp().GetHouseInformation(HouseTree.SelectedNode.Value);
if (detailTab != null && detailTab.Rows.Count > 0)
{
}
}
private void AddTreeFileData(DataTable mydt, TreeNode node)
{
foreach (DataRow dr in mydt.Rows)
{
TreeNode childNode = new TreeNode();
childNode.Text = dr["room_nm"].ToString().Trim();
childNode.Value=dr["room_id"].ToString().Trim();
childNode.ImageUrl = "../images/page_white_text.png";
childNode.ToolTip = dr["room_id"].ToString().Trim();
node.ChildNodes.Add(childNode);
childNode.SelectAction = TreeNodeSelectAction.None;
}
}
可以參考下上面的代碼,下加載2層，然後點擊那層加載那層,
