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TreeNode.Selected Property

Definition

Gets or sets a value that indicates whether the node is selected.

public:
 property bool Selected { bool get(); void set(bool value); };
public bool Selected { get; set; }
member this.Selected : bool with get, set
Public Property Selected As Boolean

Property Value

true if the node is selected; otherwise, false. The default is false.

Examples

The following code example demonstrates how to use the Selected property to select a node in the TreeView control.


<%@ 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 Button_Command(Object sender, CommandEventArgs e)
  {

    // Iterate through the child nodes of the root node and find
    // the nodes for Chapter One and Chapter Two.
    foreach(TreeNode node in LinksTreeView.Nodes[0].ChildNodes)
    {

      // Select the appropriate node based on which button was clicked.
      switch(node.Text)
      {

        case "Chapter One":
          // If the button clicked was "Chapter One", select the node 
          // using the Selected property.
          if (e.CommandName == "Chapter One")
          {
            // Select the node using the Selected property.
            node.Selected = true;
          }
          break;

        case "Chapter Two":
          // If the button clicked was "Chapter Two", select the node 
          // using the Select method.
          if (e.CommandName == "Chapter Two")
          {
            // Select the node using the Select method.
            node.Select();
          }
          break;

        default:
          // Do nothing.
          break;

      }

    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNode Selected and Select() Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNode Selected and Select() Example</h3>
    
      <asp:TreeView id="LinksTreeView"
        Font-Names= "Arial"
        ForeColor="Blue"
        SelectedNodeStyle-BackColor="Yellow" 
        ExpandDepth="2"
        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">
             
            <asp:TreeNode Text="Chapter One"
              Selected="True">
            
              <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>
      
      <br /><br />
      
      <asp:Button id="SelectChapterOneButton"
        Text="Select Chapter One"
        CommandName="Chapter One" 
        OnCommand="Button_Command"
        runat="server"/>
        
        
        
      <asp:Button id="SelectChapterTwoButton"
        Text="Select Chapter Two"
        CommandName="Chapter Two" 
        OnCommand="Button_Command"
        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 Button_Command(ByVal sender As Object, ByVal e As CommandEventArgs)

    ' Iterate through the child nodes of the root node and find
    ' the nodes for Chapter One and Chapter Two.
    Dim node As TreeNode

    For Each node In LinksTreeView.Nodes(0).ChildNodes

      ' Select the appropriate node based on which button was clicked.
      Select Case node.Text

        Case "Chapter One"
          ' If the button clicked was "Chapter One", select the node 
          ' using the Selected property.
          If e.CommandName = "Chapter One" Then

            ' Select the node using the Selected property.
            node.Selected = True

          End If

        Case "Chapter Two"
          ' If the button clicked was "Chapter Two", select the node 
          ' using the Selected method.
          If e.CommandName = "Chapter Two" Then

            ' Select the node using the Select method.
            node.Select()

          End If

        Case Else
          ' Do nothing.

      End Select

    Next

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNode Selected and Select() Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNode Selected and Select() Example</h3>
    
      <asp:TreeView id="LinksTreeView"
        Font-Names= "Arial"
        ForeColor="Blue"
        SelectedNodeStyle-BackColor="Yellow" 
        ExpandDepth="2"
        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">
             
            <asp:TreeNode Text="Chapter One"
              Selected="True">
            
              <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>
      
      <br /><br />
      
      <asp:Button id="SelectChapterOneButton"
        Text="Select Chapter One"
        CommandName="Chapter One" 
        OnCommand="Button_Command"
        runat="server"/>
        
        
        
      <asp:Button id="SelectChapterTwoButton"
        Text="Select Chapter Two"
        CommandName="Chapter Two" 
        OnCommand="Button_Command"
        runat="server"/>   

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

Remarks

Use the Selected property to specify or determine whether the node is selected.

Note

Although the property can be used to determine whether the node is selected, it is more common to use the SelectedNode property.

Only one node can be selected at a time in the TreeView control when using this property.

Note

As an alternative, you can also select the node by using the Select method.

The value of this property is stored in view state.

Applies to

See also