TreeNodeCollection.Item[Int32] Property

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

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Gets the TreeNode object at the specified index in the TreeNodeCollection object.

public:
 property System::Web::UI::WebControls::TreeNode ^ default[int] { System::Web::UI::WebControls::TreeNode ^ get(int index); };

public System.Web.UI.WebControls.TreeNode this[int index] { get; }

member this.Item(int) : System.Web.UI.WebControls.TreeNode

Default Public ReadOnly Property Item(index As Integer) As TreeNode

Parameters

index: Int32

The zero-based index of the TreeNode object to retrieve.

Property Value

TreeNode

The TreeNode object at the specified index in the TreeNodeCollection.

Examples

The following example demonstrates how to use the indexer to access an element in the TreeNodeCollection. Notice that the Nodes and ChildNodes properties return a TreeNodeCollection object.


<%@ 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 (!IsPostBack)
    {

      // Use the Add and Remove methods to programmatically 
      // remove the Appendix C node and replace it with a new 
      // node. 
      LinksTreeView.Nodes.Remove(LinksTreeView.Nodes[3]);
      LinksTreeView.Nodes.Add(new TreeNode("New Appendix C"));

      // Use the AddAt and RemoveAt methods to programmatically 
      // remove the Chapter One node and replace it with a new node.
      LinksTreeView.Nodes[0].ChildNodes.RemoveAt(0);
      LinksTreeView.Nodes[0].ChildNodes.AddAt(0, new TreeNode("New Chapter One"));

      // Use the Clear method to remove all the child nodes of the 
      // Chapter Two node.
      LinksTreeView.Nodes[0].ChildNodes[1].ChildNodes.Clear();

    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNodeCollection Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNodeCollection 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="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>

    </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 Not IsPostBack Then

      ' Use the Add and Remove methods to programmatically 
      ' remove the Appendix C node and replace it with a new 
      ' node. 
      LinksTreeView.Nodes.Remove(LinksTreeView.Nodes(3))
      LinksTreeView.Nodes.Add(New TreeNode("New Appendix C"))

      ' Use the AddAt and RemoveAt methods to programmatically 
      ' remove the Chapter One node and replace it with a new node.
      LinksTreeView.Nodes(0).ChildNodes.RemoveAt(0)
      LinksTreeView.Nodes(0).ChildNodes.AddAt(0, New TreeNode("New Chapter One"))

      ' Use the Clear method to remove all the child nodes of the 
      ' Chapter Two node.
      LinksTreeView.Nodes(0).ChildNodes(1).ChildNodes.Clear()

    End If

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNodeCollection Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNodeCollection 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="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>

    </form>
  </body>
</html>

Remarks

Use this indexer to access a TreeNode object from the TreeNodeCollection at the specified index using array notation. The indexer allows you to modify or replace a TreeNode object in the collection directly. The collection is zero-based.

Applies to

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