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TreeNodeBindingCollection.Remove(TreeNodeBinding) Method

Definition

Removes the specified TreeNodeBinding object from the TreeNodeBindingCollection object.

public:
 void Remove(System::Web::UI::WebControls::TreeNodeBinding ^ binding);
public void Remove (System.Web.UI.WebControls.TreeNodeBinding binding);
member this.Remove : System.Web.UI.WebControls.TreeNodeBinding -> unit
Public Sub Remove (binding As TreeNodeBinding)

Parameters

binding
TreeNodeBinding

The TreeNodeBinding to remove.

Examples

The following code example demonstrates how to use the Remove method to remove a TreeNodeBinding object programmatically from a TreeNodeBindingCollection object. For this example to work correctly, you must copy the XML data that is located at the end of this section to a file called Book.xml.


<%@ 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)
  {

    // Use the Remove method to remove the TreeNodeBinding object
    // for the third-level nodes (index 2).
    TreeNodeBinding oldBinding = BookTreeView.DataBindings[2];
    BookTreeView.DataBindings.Remove(oldBinding);

    // Create a new TreeNodeBinding object and set its properties.
    TreeNodeBinding newBinding = new TreeNodeBinding();
    newBinding.DataMember = "Section";
    newBinding.TextField = "Subject";

    // Use the Add method to add the TreeNodeBinding object to the 
    // DataBindings collection.
    BookTreeView.DataBindings.Add(newBinding);

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNodeBindingCollection Add and Remove Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNodeBindingCollection Add and Remove Example</h3>
    
      <asp:TreeView id="BookTreeView" 
        DataSourceID="BookXmlDataSource"
        runat="server">
         
        <DataBindings>
          <asp:TreeNodeBinding DataMember="Book" TextField="Title"/>
          <asp:TreeNodeBinding DataMember="Chapter" TextField="Heading"/>
          <asp:TreeNodeBinding DataMember="Section" TextField="Heading"/>
        </DataBindings>
         
      </asp:TreeView>

      <asp:XmlDataSource id="BookXmlDataSource"  
        DataFile="Book.xml"
        runat="server">
      </asp:XmlDataSource>
    
    </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)

    ' Use the Remove method to remove the TreeNodeBinding object
    ' for the third-level nodes (index 2).
    Dim oldBinding As TreeNodeBinding = BookTreeView.DataBindings(2)
    BookTreeView.DataBindings.Remove(oldBinding)

    ' Create a new TreeNodeBinding object and set its properties.
    Dim newBinding As TreeNodeBinding = New TreeNodeBinding
    newBinding.DataMember = "Section"
    newBinding.TextField = "Subject"

    ' Use the Add method to add the TreeNodeBinding object to the 
    ' DataBindings collection.
    BookTreeView.DataBindings.Add(newBinding)

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNodeBindingCollection Add and Remove Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNodeBindingCollection Add and Remove Example</h3>
    
      <asp:TreeView id="BookTreeView" 
        DataSourceID="BookXmlDataSource"
        runat="server">
         
        <DataBindings>
          <asp:TreeNodeBinding DataMember="Book" TextField="Title"/>
          <asp:TreeNodeBinding DataMember="Chapter" TextField="Heading"/>
          <asp:TreeNodeBinding DataMember="Section" TextField="Heading"/>
        </DataBindings>
         
      </asp:TreeView>

      <asp:XmlDataSource id="BookXmlDataSource"  
        DataFile="Book.xml"
        runat="server">
      </asp:XmlDataSource>
    
    </form>
  </body>
</html>

The following is the XML data for the preceding code example.

<Book Title="Book Title">  
    <Chapter Heading="Chapter 1">  
        <Section Heading="Section 1"  
            Subject="Subject 1">  
        </Section>  
        <Section Heading="Section 2"  
            Subject="Subject 1">  
        </Section>  
    </Chapter>  
    <Chapter Heading="Chapter 2">  
        <Section Heading="Section 1"  
            Subject="Subject 1">  
        </Section>  
    </Chapter>  
</Book>  

Remarks

Use the Remove method to remove the specified TreeNodeBinding object from the collection. All items that follow that node are then moved up to fill the vacant position. The indexes of the moved items are also updated.

As an alternative, you can remove a node at a specific index using the RemoveAt method. You can also remove every node in the collection using the Clear method.

Applies to

See also