TreeNode.Selected Proprietà
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Ottiene o imposta un valore che indica se il nodo è selezionato.
public:
property bool Selected { bool get(); void set(bool value); };public bool Selected { get; set; }member this.Selected : bool with get, setPublic Property Selected As BooleanValore della proprietà
true se il nodo è selezionato; in caso contrario, false. Il valore predefinito è false.
Esempio
Nell'esempio di codice seguente viene illustrato come usare la Selected proprietà per selezionare un nodo nel TreeView controllo.
<%@ 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_Command(Object sender, CommandEventArgs e)
{
// Iterate through the child nodes of the root node and find
// the nodes for Chapter One and Chapter Two.
foreach(TreeNode node in LinksTreeView.Nodes[0].ChildNodes)
{
// Select the appropriate node based on which button was clicked.
switch(node.Text)
{
case "Chapter One":
// If the button clicked was "Chapter One", select the node
// using the Selected property.
if (e.CommandName == "Chapter One")
{
// Select the node using the Selected property.
node.Selected = true;
}
break;
case "Chapter Two":
// If the button clicked was "Chapter Two", select the node
// using the Select method.
if (e.CommandName == "Chapter Two")
{
// Select the node using the Select method.
node.Select();
}
break;
default:
// Do nothing.
break;
}
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>TreeNode Selected and Select() Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>TreeNode Selected and Select() Example</h3>
<asp:TreeView id="LinksTreeView"
Font-Names= "Arial"
ForeColor="Blue"
SelectedNodeStyle-BackColor="Yellow"
ExpandDepth="2"
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">
<asp:TreeNode Text="Chapter One"
Selected="True">
<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:Button id="SelectChapterOneButton"
Text="Select Chapter One"
CommandName="Chapter One"
OnCommand="Button_Command"
runat="server"/>
<asp:Button id="SelectChapterTwoButton"
Text="Select Chapter Two"
CommandName="Chapter Two"
OnCommand="Button_Command"
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_Command(ByVal sender As Object, ByVal e As CommandEventArgs)
' Iterate through the child nodes of the root node and find
' the nodes for Chapter One and Chapter Two.
Dim node As TreeNode
For Each node In LinksTreeView.Nodes(0).ChildNodes
' Select the appropriate node based on which button was clicked.
Select Case node.Text
Case "Chapter One"
' If the button clicked was "Chapter One", select the node
' using the Selected property.
If e.CommandName = "Chapter One" Then
' Select the node using the Selected property.
node.Selected = True
End If
Case "Chapter Two"
' If the button clicked was "Chapter Two", select the node
' using the Selected method.
If e.CommandName = "Chapter Two" Then
' Select the node using the Select method.
node.Select()
End If
Case Else
' Do nothing.
End Select
Next
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>TreeNode Selected and Select() Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>TreeNode Selected and Select() Example</h3>
<asp:TreeView id="LinksTreeView"
Font-Names= "Arial"
ForeColor="Blue"
SelectedNodeStyle-BackColor="Yellow"
ExpandDepth="2"
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">
<asp:TreeNode Text="Chapter One"
Selected="True">
<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:Button id="SelectChapterOneButton"
Text="Select Chapter One"
CommandName="Chapter One"
OnCommand="Button_Command"
runat="server"/>
<asp:Button id="SelectChapterTwoButton"
Text="Select Chapter Two"
CommandName="Chapter Two"
OnCommand="Button_Command"
runat="server"/>
</form>
</body>
</html>
Commenti
Utilizzare la Selected proprietà per specificare o determinare se il nodo è selezionato.
Nota
Anche se la proprietà può essere usata per determinare se il nodo è selezionato, è più comune usare la SelectedNode proprietà.
È possibile selezionare un solo nodo alla volta nel TreeView controllo quando si usa questa proprietà.
Nota
In alternativa, è anche possibile selezionare il nodo usando il Select metodo .
Il valore di questa proprietà viene archiviato nello stato di visualizzazione.