TreeView.SelectedNode Propriedade

Definição

Obtém um objeto TreeNode que representa o nó selecionado no controle TreeView.Gets a TreeNode object that represents the selected node in the TreeView control.

public:
 property System::Web::UI::WebControls::TreeNode ^ SelectedNode { System::Web::UI::WebControls::TreeNode ^ get(); };
[System.ComponentModel.Browsable(false)]
public System.Web.UI.WebControls.TreeNode SelectedNode { get; }
[<System.ComponentModel.Browsable(false)>]
member this.SelectedNode : System.Web.UI.WebControls.TreeNode
Public ReadOnly Property SelectedNode As TreeNode

Valor da propriedade

TreeNode

Um TreeNode que representa o nó selecionado no TreeView.A TreeNode that represents the selected node in the TreeView.

Atributos

Exemplos

O exemplo de código a seguir demonstra como usar a SelectedNode propriedade para determinar o valor do nó selecionado no TreeView controle.The following code example demonstrates how to use the SelectedNode property to determine the value of the selected node in the TreeView control.


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

        Message.Text = "You selected: " + LinksTreeView.SelectedNode.Text;

    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >

    <head runat="server">
    <title>TreeView SelectedNodeStyle Example</title>
</head>
<body>
        <form id="form1" runat="server">
        
            <h3>TreeView SelectedNodeStyle Example</h3>

            <asp:TreeView id="LinksTreeView"
                Font-Names= "Arial"
                ForeColor="Blue"
                SelectedNodeStyle-ForeColor="Green"
                SelectedNodeStyle-VerticalPadding="0"
                OnSelectedNodeChanged="Select_Change"   
                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>
            
            <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 Select_Change(ByVal sender As Object, ByVal e As EventArgs)

        Message.Text = "You selected: " & LinksTreeView.SelectedNode.Text

    End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >

    <head runat="server">
    <title>TreeView SelectedNodeStyle Example</title>
</head>
<body>
        <form id="form1" runat="server">
        
            <h3>TreeView SelectedNodeStyle Example</h3>
            
            <asp:TreeView id="LinksTreeView"
                Font-Names= "Arial"
                ForeColor="Blue"
                SelectedNodeStyle-ForeColor="Green"
                SelectedNodeStyle-VerticalPadding="0"
                OnSelectedNodeChanged="Select_Change"   
                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>
            
            <br /><br />
            
            <asp:Label id="Message" runat="server"/>
            
        </form>
    </body>
</html>

Comentários

O texto de um nó no TreeView controle pode estar em um dos dois modos: modo de seleção e modo de navegação.The text of a node in the TreeView control can be in one of two modes: selection mode and navigation mode. Por padrão, um nó está no modo de seleção.By default, a node is in selection mode. Para colocar um nó no modo de navegação, defina a NavigateUrl propriedade para o nó com um valor diferente de uma cadeia de caracteres vazia ("").To put a node into navigation mode, set the NavigateUrl property for the node to a value other than an empty string (""). Para colocar um nó no modo de seleção, defina a NavigateUrl propriedade para o nó como cadeia de caracteres vazia ("").To put a node into selection mode, set the NavigateUrl property for the node to empty string ("").

Quando um nó está no modo de seleção, o usuário pode selecionar um nó clicando no texto no nó.When a node is in selection mode, the user can select a node by clicking on the text in the node. Use a SelectedNode propriedade para determinar qual nó está selecionado no TreeView controle.Use the SelectedNode property to determine which node is selected in the TreeView control.

Observação

Um nó não pode ser selecionado quando o TreeView controle exibe hiperlinks.A node cannot be selected when the TreeView control displays hyperlinks. Quando os hiperlinks são exibidos, a SelectedNode propriedade sempre retorna null .When hyperlinks are displayed, the SelectedNode property always returns null.

Quando o usuário seleciona um nó diferente no TreeView controle clicando no texto no novo nó, o SelectedNodeChanged evento é gerado, por padrão.When the user selects a different node in the TreeView control by clicking the text in the new node, the SelectedNodeChanged event is raised, by default. Você pode especificar um evento diferente definindo a SelectAction propriedade para a propriedade.You can specify a different event by setting the SelectAction property for the property. A tabela a seguir lista as opções disponíveis.The following table lists the available options.

Ação de seleçãoSelection action DescriçãoDescription
Expand Alterna o nó entre expandido e recolhido.Toggles the node between expanded and collapsed. Gera o TreeNodeExpanded TreeNodeCollapsed evento ou, conforme apropriado.Raises the TreeNodeExpanded or TreeNodeCollapsed event, as appropriate.
None Não aciona nenhum evento quando um nó é selecionado.Raises no events when a node is selected.
Select Aciona o evento SelectedNodeChanged quando um nó é selecionado.Raises the SelectedNodeChanged event when a node is selected.
SelectExpand Aciona os eventos SelectedNodeChanged e TreeNodeExpanded quando um nó é selecionado.Raises both the SelectedNodeChanged and TreeNodeExpanded events when a node is selected. Os nós são expandidos apenas, nunca recolhidos.Nodes are only expanded, never collapsed.

Observação

O HoverNodeStyle não é renderizado para um nó com sua SelectAction propriedade definida como TreeNodeSelectAction.None .The HoverNodeStyle is not rendered for a node with its SelectAction property set to TreeNodeSelectAction.None.

Aplica-se a

Confira também