TreeNodeCollection.Add(TreeNode) Metodo

Definizione

Accoda l'oggetto specificato TreeNode alla fine dell'oggetto TreeNodeCollection .

public:
 void Add(System::Web::UI::WebControls::TreeNode ^ child);
public void Add(System.Web.UI.WebControls.TreeNode child);
member this.Add : System.Web.UI.WebControls.TreeNode -> unit
Public Sub Add (child As TreeNode)

Parametri

child
TreeNode

Oggetto TreeNode da accodare.

Esempio

Nell'esempio seguente viene illustrato come usare il Add metodo per aggiungere a livello di codice un nodo a TreeNodeCollection. Si noti che le Nodes proprietà e ChildNodes restituiscono ogni TreeNodeCollection oggetto .


<%@ 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>

Commenti

Utilizzare il Add metodo per aggiungere l'oggetto specificato TreeNode alla fine di TreeNodeCollection.

Note

Il TreeNodeCollection consente di aggiungere riferimenti Null (Nothing in Visual Basic), nonché oggetti TreeNode duplicati.

In alternativa, è possibile inserire un TreeNode oggetto in TreeNodeCollection in corrispondenza di un indice specifico usando il AddAt metodo .

Si applica a

Vedi anche