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TreeNode.Selected Eigenschaft

Definition

Ruft einen Wert ab, der angibt, ob der Knoten ausgewählt ist, oder legt diesen Wert fest.

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

Eigenschaftswert

Boolean

true, wenn der Knoten ausgewählt ist, andernfalls false. Der Standardwert ist false.

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie Die Selected Eigenschaft zum Auswählen eines Knotens TreeView im Steuerelement verwendet wird.


<%@ 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>

Hinweise

Verwenden Sie die Selected Eigenschaft, um anzugeben oder zu bestimmen, ob der Knoten ausgewählt ist.

Hinweis

Obwohl die Eigenschaft verwendet werden kann, um zu bestimmen, ob der Knoten ausgewählt ist, ist es häufiger, die SelectedNode Eigenschaft zu verwenden.

Bei Verwendung dieser Eigenschaft kann jeweils nur ein Knoten im TreeView Steuerelement ausgewählt werden.

Hinweis

Alternativ können Sie den Knoten auch mithilfe der Select Methode auswählen.

Der Wert dieser Eigenschaft wird im Ansichtszustand gespeichert.

Gilt für

Siehe auch