Treeview问题!

Question

如何动态的指定展开到第几级?
比如我有个文本框,一个按钮,一棵树,我在文本框中输入2,点击按钮就展开树到第二级,输入3,点按钮就展开到第三级,怎么做?

Answer 1

treeview.StaticDisplayLevels = int.parse(textbox1.text.trim());

Answer 2

大体如下 
private void ExTreeByLever(TreeNode tn  ,int lever)
        {
            foreach (TreeNode sub in tn.Nodes)
            {
                tn.Expand();
                if (tn.Level < lever)
                {
                    ExTreeByLever(tn, lever);
                }
            }
        }

Answer 3

貌似不行啊:CS0117: “System.Web.UI.WebControls.TreeView”并不包含“StaticDisplayLevels”的定义能说一下怎么用吗?

Answer 4

CS0117: “System.Web.UI.WebControls.TreeNode”并不包含“Level”的定义

Answer 5

自己写个方法获取节点的lever吧 俺弄winform的 

Answer 6

zhchg6666 ,你的方法不太好使.

Answer 7

zhchg6666 ,你的方法我改了改,能实现向下展开的了,也就是输入2,展开到了第二级,再输入3,展开到了第三级,但是再输入2,就无法收起到第二级,因为只是写了sub.Expand();只能向下展开,不能向上收起.
改的代码如下:
    
    private void ExTreeByLever(TreeNode tn, int lever)
    {
        foreach (TreeNode sub in tn.ChildNodes)
        {
            if (sub.Depth < lever)
            {
                sub.Expand();
            } 
            ExTreeByLever(sub, lever);
        }
    }    //调用:
    ExTreeByLever(this.TreeView1.Nodes[0], int.Parse(this.iptDepth.Value.Trim()));

Answer 8

搞定!马上结贴!    private void ExTreeByLever(TreeNode tn, int lever)
    {
        foreach (TreeNode sub in tn.ChildNodes)
        {
            if (sub.Depth < lever)
            {
                sub.Expand();
            }
            else
            {
                sub.ToggleExpandState();
            }
            ExTreeByLever(sub, lever);
        }
    }    //调用:
    ExTreeByLever(this.TreeView1.Nodes[0], int.Parse(this.iptDepth.Value.Trim()));

Answer 9

这应该是你要求的!记得给分鼓励一下.
    protected void Button1_Click(object sender, EventArgs e)
    {
        int i = Convert.ToInt32(TextBox2.Text);
        int dth = 0;            foreach (TreeNode TN in TreeView2.Nodes)
            {
                if (dth < i)
                {
                    TN.Expand();
                    TreeNodeExpand(TN, i);
                }
                else
                {
                    TN.Expanded = false;
                    TreeNodeExpand(TN, i);
                }
                              
            }                
    }    public void TreeNodeExpand(TreeNode TreeN,int dth)
    {            foreach (TreeNode no in TreeN.ChildNodes)
            {
                if (no.Depth < dth)
                {
                    no.Expand();
                    TreeNodeExpand(no, dth);
                }
                else
                {
                    no.Expanded = false;
                    TreeNodeExpand(no, dth);
                }
            }    }

Answer 10

lonelygames 的代码又启发了我"no.Expanded = false; ";
ToggleExpandState()这个只是切换节点的展开和折叠状态,并不是折叠节点.修改如下:    private void ExTreeByLever(TreeNode tn, int lever)
    {
        foreach (TreeNode sub in tn.ChildNodes)
        {
            if (sub.Depth < lever)
            {
                sub.Expand();
            }
            else
            {
                sub.Expanded = false;
            }
            ExTreeByLever(sub, lever);
        }
    }    //调用:
    ExTreeByLever(this.TreeView1.Nodes[0], int.Parse(this.iptDepth.Value.Trim()));
感谢lonelygames!