TreeNode.ChildNodes 属性
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
获取 TreeNodeCollection 集合,该集合包含当前节点的第一级子节点。
public:
property System::Web::UI::WebControls::TreeNodeCollection ^ ChildNodes { System::Web::UI::WebControls::TreeNodeCollection ^ get(); };
[System.ComponentModel.Browsable(false)]
[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerDefaultProperty)]
public System.Web.UI.WebControls.TreeNodeCollection ChildNodes { get; }
[<System.ComponentModel.Browsable(false)>]
[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerDefaultProperty)>]
member this.ChildNodes : System.Web.UI.WebControls.TreeNodeCollection
Public ReadOnly Property ChildNodes As TreeNodeCollection
属性值
TreeNodeCollection,包含当前节点的第一级子节点。
- 属性
示例
下面的代码示例演示如何使用 ChildNodes 属性遍历树。
<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Page_Load(Object sender, EventArgs e)
{
// If the TreeView control contains any root nodes, perform a
// preorder traversal of the tree and display the text of each node.
if(LinksTreeView.Nodes.Count > 0)
{
// Iterate through the root nodes in the Nodes property.
for(int i=0; i<LinksTreeView.Nodes.Count; i++)
{
// Display the nodes.
DisplayChildNodeText(LinksTreeView.Nodes[i]);
}
}
else
{
Message.Text = "The TreeView control does not have any nodes.";
}
}
void DisplayChildNodeText(TreeNode node)
{
// Display the node's text value.
Message.Text += node.Text + "<br />";
// Iterate through the child nodes of the parent node passed into
// this method and display their values.
for(int i=0; i<node.ChildNodes.Count; i++)
{
// Recursively call the DisplayChildNodeText method to
// traverse the tree and display all the child nodes.
DisplayChildNodeText(node.ChildNodes[i]);
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>TreeNodeCollection Count Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>TreeNodeCollection Count Example</h3>
<asp:TreeView id="LinksTreeView"
Font-Names= "Arial"
ForeColor="Blue"
runat="server">
<LevelStyles>
<asp:TreeNodeStyle ChildNodesPadding="10"
Font-Bold="true"
Font-Size="12pt"
ForeColor="DarkGreen"/>
<asp:TreeNodeStyle ChildNodesPadding="5"
Font-Bold="true"
Font-Size="10pt"/>
<asp:TreeNodeStyle ChildNodesPadding="5"
Font-UnderLine="true"
Font-Size="10pt"/>
<asp:TreeNodeStyle ChildNodesPadding="10"
Font-Size="8pt"/>
</LevelStyles>
<Nodes>
<asp:TreeNode Text="Table of Contents"
Expanded="true">
<asp:TreeNode Text="Chapter One">
<asp:TreeNode Text="Section 1.0">
<asp:TreeNode Text="Topic 1.0.1"/>
<asp:TreeNode Text="Topic 1.0.2"/>
<asp:TreeNode Text="Topic 1.0.3"/>
</asp:TreeNode>
<asp:TreeNode Text="Section 1.1">
<asp:TreeNode Text="Topic 1.1.1"/>
<asp:TreeNode Text="Topic 1.1.2"/>
<asp:TreeNode Text="Topic 1.1.3"/>
<asp:TreeNode Text="Topic 1.1.4"/>
</asp:TreeNode>
</asp:TreeNode>
<asp:TreeNode Text="Chapter Two">
<asp:TreeNode Text="Section 2.0">
<asp:TreeNode Text="Topic 2.0.1">
<asp:TreeNode Text="Subtopic 1"/>
<asp:TreeNode Text="Subtopic 2"/>
</asp:TreeNode>
<asp:TreeNode Text="Topic 2.0.2"/>
</asp:TreeNode>
</asp:TreeNode>
</asp:TreeNode>
<asp:TreeNode Text="Appendix A" />
<asp:TreeNode Text="Appendix B" />
<asp:TreeNode Text="Appendix C" />
</Nodes>
</asp:TreeView>
<br /><br />
<asp:Label id="Message"
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' If the TreeView control contains any root nodes, perform a
' preorder traversal of the tree and display the text of each node.
If LinksTreeView.Nodes.Count > 0 Then
' Iterate through the root nodes in the Nodes property.
Dim i As Integer
For i = 0 To LinksTreeView.Nodes.Count - 1
' Display the nodes.
DisplayChildNodeText(LinksTreeView.Nodes(i))
Next i
Else
Message.Text = "The TreeView control does not have any nodes."
End If
End Sub
Sub DisplayChildNodeText(ByVal node As TreeNode)
' Display the node's text value.
Message.Text &= node.Text & "<br />"
' Iterate through the child nodes of the parent node passed into
' this method and display their values.
Dim i As Integer
For i = 0 To node.ChildNodes.Count - 1
' Recursively call the DisplayChildNodeText method to
' traverse the tree and display all the child nodes.
DisplayChildNodeText(node.ChildNodes(i))
Next i
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>TreeNodeCollection Count Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>TreeNodeCollection Count Example</h3>
<asp:TreeView id="LinksTreeView"
Font-Names= "Arial"
ForeColor="Blue"
runat="server">
<LevelStyles>
<asp:TreeNodeStyle ChildNodesPadding="10"
Font-Bold="true"
Font-Size="12pt"
ForeColor="DarkGreen"/>
<asp:TreeNodeStyle ChildNodesPadding="5"
Font-Bold="true"
Font-Size="10pt"/>
<asp:TreeNodeStyle ChildNodesPadding="5"
Font-UnderLine="true"
Font-Size="10pt"/>
<asp:TreeNodeStyle ChildNodesPadding="10"
Font-Size="8pt"/>
</LevelStyles>
<Nodes>
<asp:TreeNode Text="Table of Contents"
Expanded="true">
<asp:TreeNode Text="Chapter One">
<asp:TreeNode Text="Section 1.0">
<asp:TreeNode Text="Topic 1.0.1"/>
<asp:TreeNode Text="Topic 1.0.2"/>
<asp:TreeNode Text="Topic 1.0.3"/>
</asp:TreeNode>
<asp:TreeNode Text="Section 1.1">
<asp:TreeNode Text="Topic 1.1.1"/>
<asp:TreeNode Text="Topic 1.1.2"/>
<asp:TreeNode Text="Topic 1.1.3"/>
<asp:TreeNode Text="Topic 1.1.4"/>
</asp:TreeNode>
</asp:TreeNode>
<asp:TreeNode Text="Chapter Two">
<asp:TreeNode Text="Section 2.0">
<asp:TreeNode Text="Topic 2.0.1">
<asp:TreeNode Text="Subtopic 1"/>
<asp:TreeNode Text="Subtopic 2"/>
</asp:TreeNode>
<asp:TreeNode Text="Topic 2.0.2"/>
</asp:TreeNode>
</asp:TreeNode>
</asp:TreeNode>
<asp:TreeNode Text="Appendix A" />
<asp:TreeNode Text="Appendix B" />
<asp:TreeNode Text="Appendix C" />
</Nodes>
</asp:TreeView>
<br /><br />
<asp:Label id="Message"
runat="server"/>
</form>
</body>
</html>
注解
使用 ChildNodes 属性获取包含当前节点的第一 TreeNodeCollection 级子节点的集合。 此集合通常用于循环访问所有第一级子节点,或访问当前节点的特定一级子节点。
该 ChildNodes 属性还可用于以编程方式管理当前节点中的第一级子节点。 可以从集合中添加、插入、删除和检索 TreeNode 对象。 下次刷新页面时,集合的任何更新将自动反映在控件中 TreeView 。
若要进一步访问树中的子节点,请使用 ChildNodes 下一级子节点的属性在节点级别下导航。