TreeView.ShowExpandCollapse Property

Definition

Ottiene o imposta un valore che indica se gli indicatori di espansione dei nodi sono visualizzati.Gets or sets a value indicating whether expansion node indicators are displayed.

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

Property Value

Boolean

true per visualizzare gli indicatori di espansione dei nodi; in caso contrario, false.true to show the expansion node indicators; otherwise, false. Il valore predefinito è true.The default is true.

Examples

Nell'esempio di codice riportato di seguito viene illustrato come utilizzare la proprietà ShowExpandCollapse per visualizzare e nascondere le icone del nodo di espansione.The following code example demonstrates how to use the ShowExpandCollapse property to show and hide the expansion node icons.


<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeView ShowExpandCollapse Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeView ShowExpandCollapse Example</h3>
    
      <asp:TreeView id="LinksTreeView"
        Font-Names= "Arial"
        ForeColor="Blue"
        ExpandDepth="2"
        ShowExpandCollapse="true" 
        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">
            
              <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">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeView ShowExpandCollapse Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeView ShowExpandCollapse Example</h3>
    
      <asp:TreeView id="LinksTreeView"
        Font-Names= "Arial"
        ForeColor="Blue"
        ExpandDepth="2"
        ShowExpandCollapse="true" 
        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">
            
              <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

Gli indicatori del nodo di espansione vengono utilizzati per indicare se un nodo è espanso, compresso o non espandibile.Expansion node indicators are used to show whether a node is expanded, collapsed, or non-expandable. Utilizzare la proprietà ShowExpandCollapse per specificare se gli indicatori del nodo di espansione vengono visualizzati nel controllo TreeView.Use the ShowExpandCollapse property to specify whether the expansion node indicators are displayed in the TreeView control.

Quando la proprietà ShowExpandCollapse è impostata su true, il controllo TreeView Visualizza un segno più (+) o un segno meno (-) o un'immagine segnaposto accanto a un nodo per indicare se il nodo è espandibile, comprimibile o non espandibile, rispettivamente.When the ShowExpandCollapse property is set to true, the TreeView control displays a plus sign (+) or minus sign (-) or a placeholder image next to a node to indicate whether the node is expandable, collapsible, or non-expandable, respectively. È possibile specificare immagini personalizzate impostando prima la proprietà ImageSet su TreeViewImageSet.Custome quindi impostando le proprietà NoExpandImageUrl, ExpandImageUrle CollapseImageUrl sugli URL delle immagini personalizzate.You can specify custom images by first setting the ImageSet property to TreeViewImageSet.Custom, and then setting the NoExpandImageUrl, ExpandImageUrl, and CollapseImageUrl properties to the URLs of the custom images. Se non viene specificata alcuna immagine, vengono utilizzate le immagini predefinite.If no images are specified, the default images are used.

Il valore di questa proprietà viene archiviato nello stato di visualizzazione.The value of this property is stored in view state.

Applies to

See also