TreeView.FindNode(String) Metodo

  • Riferimento

Definizione

Spazio dei nomi:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Consente di recuperare l'oggetto TreeNode nel controllo TreeView in corrispondenza del percorso del valore specificato.

public:
 System::Web::UI::WebControls::TreeNode ^ FindNode(System::String ^ valuePath);
public System.Web.UI.WebControls.TreeNode FindNode (string valuePath);
member this.FindNode : string -> System.Web.UI.WebControls.TreeNode
Public Function FindNode (valuePath As String) As TreeNode

Parametri

valuePath
String

Percorso del valore di un nodo.

Restituisce

TreeNode

Oggetto TreeNode in corrispondenza del percorso del valore specificato.

Esempio

Nell'esempio di codice seguente viene illustrato come usare il FindNode metodo per recuperare un nodo dal TreeView controllo .

Importante

L'esempio include una casella di testo che accetta l'input dell'utente e rappresenta quindi una potenziale minaccia alla sicurezza. Per impostazione predefinita, le pagine Web ASP.NET verificano che l'input dell'utente non includa script o elementi HTML. Per altre informazioni, vedere Cenni preliminari sugli attacchi tramite script.


<%@ 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_Click(Object sender, EventArgs e)
  {

    // Find the node specified by the user.
    TreeNode node = LinksTreeView.FindNode(Server.HtmlEncode(ValuePathText.Text));

    if (node != null)
    {
      // Indicate that the node was found.
      Message.Text = "The specified node (" + node.ValuePath + ") was found.";
    }
    else
    {
      // Indicate that the node is not in the TreeView control.
      Message.Text = "The specified node (" + ValuePathText.Text + ") is not in this TreeView control.";
    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml">
  <head runat="server">
    <title>TreeView FindNode Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeView FindNode Example</h3>
    
      <asp:TreeView id="LinksTreeView"
        PathSeparator="/"
        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"
            SelectAction="None">
             
            <asp:TreeNode Text="Chapter One" Value="Chapter One">
            
              <asp:TreeNode Text="Section 1.0" Value="Section 1.0">
              
                <asp:TreeNode Text="Topic 1.0.1" Value="Topic 1.0.1"/>
                <asp:TreeNode Text="Topic 1.0.2" Value="Topic 1.0.2"/>
                <asp:TreeNode Text="Topic 1.0.3" Value="Topic 1.0.3"/>
              
              </asp:TreeNode>
              
              <asp:TreeNode Text="Section 1.1">
              
                <asp:TreeNode Text="Topic 1.1.1" Value="Topic 1.1.1"/>
                <asp:TreeNode Text="Topic 1.1.2" Value="Topic 1.1.2"/>
                <asp:TreeNode Text="Topic 1.1.3" Value="Topic 1.1.3"/>
                <asp:TreeNode Text="Topic 1.1.4" Value="Topic 1.1.4"/>
              
              </asp:TreeNode>
            
            </asp:TreeNode>
            
            <asp:TreeNode Text="Chapter Two" Value="Chapter Two">
            
              <asp:TreeNode Text="Section 2.0" Value="Section 2.0">
              
                <asp:TreeNode Text="Topic 2.0.1" Value="Topic 2.0.1"/>
                <asp:TreeNode Text="Topic 2.0.2" Value="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>
      
      <hr/>
      
      <br/><br/>
      
      Enter the value path of the node to locate. <br/>
      Use a forward slash (/) to delimit each node value.<br/>
      <asp:TextBox id="ValuePathText" 
        Text="Table of Contents/Chapter One/Section 1.0"
        Width="50%" 
        runat="server"/>
         
      <br/><br/>
      
      <asp:Button id="Submit"
        Text="Find Node"
        OnClick="Button_Click"  
        runat="server"/>
      
      <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 Button_Click(ByVal sender As Object, ByVal e As EventArgs)

    ' Find the node specified by the user.
    Dim node As TreeNode = LinksTreeView.FindNode(Server.HtmlEncode(ValuePathText.Text))

    If Not node Is Nothing Then
   
      ' Indicate that the node was found.
      Message.Text = "The specified node (" & node.ValuePath & ") was found."

    Else

      ' Indicate that the node is not in the TreeView control.
      Message.Text = "The specified node (" & ValuePathText.Text & ") is not in this TreeView control."

    End If

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml">
  <head runat="server">
    <title>TreeView FindNode Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeView FindNode Example</h3>
    
      <asp:TreeView id="LinksTreeView"
        PathSeparator="/"
        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"
            SelectAction="None">
             
            <asp:TreeNode Text="Chapter One" Value="Chapter One">
            
              <asp:TreeNode Text="Section 1.0" Value="Section 1.0">
              
                <asp:TreeNode Text="Topic 1.0.1" Value="Topic 1.0.1"/>
                <asp:TreeNode Text="Topic 1.0.2" Value="Topic 1.0.2"/>
                <asp:TreeNode Text="Topic 1.0.3" Value="Topic 1.0.3"/>
              
              </asp:TreeNode>
              
              <asp:TreeNode Text="Section 1.1">
              
                <asp:TreeNode Text="Topic 1.1.1" Value="Topic 1.1.1"/>
                <asp:TreeNode Text="Topic 1.1.2" Value="Topic 1.1.2"/>
                <asp:TreeNode Text="Topic 1.1.3" Value="Topic 1.1.3"/>
                <asp:TreeNode Text="Topic 1.1.4" Value="Topic 1.1.4"/>
              
              </asp:TreeNode>
            
            </asp:TreeNode>
            
            <asp:TreeNode Text="Chapter Two" Value="Chapter Two">
            
              <asp:TreeNode Text="Section 2.0" Value="Section 2.0">
              
                <asp:TreeNode Text="Topic 2.0.1" Value="Topic 2.0.1"/>
                <asp:TreeNode Text="Topic 2.0.2" Value="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>
      
      <hr/>
      
      <br/><br/>
      
      Enter the value path of the node to locate. <br/>
      Use a forward slash (/) to delimit each node value.<br/>
      <asp:TextBox id="ValuePathText" 
        Text="Table of Contents/Chapter One/Section 1.0"
        Width="50%" 
        runat="server"/>
         
      <br/><br/>
      
      <asp:Button id="Submit"
        Text="Find Node"
        OnClick="Button_Click"  
        runat="server"/>
      
      <br/><br/>
      
      <asp:Label id="Message" runat="server"/>

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

Commenti

Usare il FindNode metodo per ottenere un nodo dal TreeView controllo in corrispondenza del percorso del valore specificato. Il percorso del valore contiene un elenco delimitatore separato da valori di nodo che formano un percorso dal nodo radice al nodo corrente. Ogni nodo archivia il percorso del valore nella ValuePath proprietà . La PathSeparator proprietà specifica il carattere delimitatore utilizzato per separare i valori del nodo.

Si applica a

Vedi anche