TreeView.ShowExpandCollapse Property

Definition

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

true to show the expansion node indicators; otherwise, false. The default is true.

Examples

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

Expansion node indicators are used to show whether a node is expanded, collapsed, or non-expandable. Use the ShowExpandCollapse property to specify whether the expansion node indicators are displayed in the TreeView control.

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. 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. If no images are specified, the default images are used.

The value of this property is stored in view state.

Applies to

See also