Proprietà TreeView.ShowRootLines (System.Windows.Forms)

Cambia visualizzazione:
Classica
Lightweight
ScriptFree
Riferimento a .NET Framework
Proprietà TreeView.ShowRootLines

Ottiene o imposta un valore che indica se vengono visualizzate linee tra i nodi della struttura che rappresentano il primo livello della visualizzazione struttura.

Spazio dei nomi: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

Sintassi
Visual Basic - (Dichiarazione)
Public Property ShowRootLines As Boolean
Visual Basic (Utilizzo)
Dim instance As TreeView
Dim value As Boolean

value = instance.ShowRootLines

instance.ShowRootLines = value
C#
public bool ShowRootLines { get; set; }
C++
public:
property bool ShowRootLines {
	bool get ();
	void set (bool value);
}
J#
/** @property */
public boolean get_ShowRootLines ()

/** @property */
public void set_ShowRootLines (boolean value)
JScript
public function get ShowRootLines () : boolean

public function set ShowRootLines (value : boolean)

Valore proprietà

true se vengono visualizzate linee tra i nodi della struttura che rappresentano il primo livello della visualizzazione struttura; in caso contrario, false. Il valore predefinito è true.
Note

Se la proprietà ShowRootLines è false, i pulsanti più (+) e meno (-) non saranno visualizzati accanto ai nodi principali della struttura e la proprietà ShowPlusMinus non avrà alcun effetto.

Esempio

Nell'esempio di codice riportato di seguito viene illustrato come utilizzare l'enumerazione BorderStyle e le proprietà BorderStyle, ShowLines, Scrollable, HideSelection e ShowRootLines. Per eseguire l'esempio, incollare il codice riportato di seguito in un form e chiamare il metodo InitializeTreeView nel costruttore del form o nel metodo Load.

Visual Basic

' Declare the TreeView control.
Friend WithEvents TreeView1 As System.Windows.Forms.TreeView

' Initialize the TreeView to blend with the form, giving it the 
' same color as the form and no border.
Private Sub InitializeTreeView()

    ' Create a new TreeView control and set the location and size.
    Me.TreeView1 = New System.Windows.Forms.TreeView
    Me.TreeView1.Location = New System.Drawing.Point(72, 48)
    Me.TreeView1.Size = New System.Drawing.Size(200, 200)

    ' Set the BorderStyle property to none, the BackColor property to  
    ' the form's backcolor, and the Scrollable property to false.  
    ' This allows the TreeView to blend in form.
    Me.TreeView1.BorderStyle = BorderStyle.None
    Me.TreeView1.BackColor = Me.BackColor
    Me.TreeView1.Scrollable = False

    
    ' Set the ShowRootLines and ShowLines properties to false to 
    ' give the TreeView a list-like appearance.
    Me.TreeView1.ShowRootLines = False
    Me.TreeView1.ShowLines = False

    ' Add the nodes.
    Me.TreeView1.Nodes.AddRange(New System.Windows.Forms.TreeNode() _
        {New System.Windows.Forms.TreeNode("Features", _
        New System.Windows.Forms.TreeNode() _
        {New System.Windows.Forms.TreeNode("Full Color"), _
        New System.Windows.Forms.TreeNode("Project Wizards"), _
        New System.Windows.Forms.TreeNode("Visual C# and Visual Basic Support")}), _
        New System.Windows.Forms.TreeNode("System Requirements", _
        New System.Windows.Forms.TreeNode() _
        {New System.Windows.Forms.TreeNode _
        ("Pentium 133 MHz or faster processor "), _
        New System.Windows.Forms.TreeNode("Windows 98 or later"), _
        New System.Windows.Forms.TreeNode("100 MB Disk space")})})

    ' Set the tab index and add the TreeView to the form.
    Me.TreeView1.TabIndex = 0
    Me.Controls.Add(Me.TreeView1)
End Sub
C#

// Declare the TreeView control.
internal System.Windows.Forms.TreeView TreeView1;

// Initialize the TreeView to blend with the form, giving it the 
// same color as the form and no border.
private void InitializeTreeView()
{

    // Create a new TreeView control and set the location and size.
    this.TreeView1 = new System.Windows.Forms.TreeView();
    this.TreeView1.Location = new System.Drawing.Point(72, 48);
    this.TreeView1.Size = new System.Drawing.Size(200, 200);

    // Set the BorderStyle property to none, the BackColor property to  
    // the form's backcolor, and the Scrollable property to false.  
    // This allows the TreeView to blend in form.

    this.TreeView1.BorderStyle = BorderStyle.None;
    this.TreeView1.BackColor = this.BackColor;
    this.TreeView1.Scrollable = false;

    // Set the HideSelection property to false to keep the 
    // selection highlighted when the user leaves the control. 
    // This helps it blend with form.
    this.TreeView1.HideSelection = false;

    // Set the ShowRootLines and ShowLines properties to false to 
    // give the TreeView a list-like appearance.
    this.TreeView1.ShowRootLines = false;
    this.TreeView1.ShowLines = false;

    // Add the nodes.
    this.TreeView1.Nodes.AddRange(new TreeNode[]
        {new TreeNode("Features", 
            new TreeNode[]{
            new TreeNode("Full Color"), 
            new TreeNode("Project Wizards"), 
            new TreeNode("Visual C# and Visual Basic Support")}), 
            new TreeNode("System Requirements", 
            new TreeNode[]{
                new TreeNode("Pentium 133 MHz or faster processor "),
                new TreeNode("Windows 98 or later"), 
                new TreeNode("100 MB Disk space")})
        });

    // Set the tab index and add the TreeView to the form.
    this.TreeView1.TabIndex = 0;
    this.Controls.Add(this.TreeView1);
}
J#
// Declare the TreeView control.
System.Windows.Forms.TreeView treeView1;

// Initialize the TreeView to blend with the form, giving it the 
// same color as the form and no border.
private void InitializeTreeView()
{
    // Create a new TreeView control and set the location and size.
    this.treeView1 = new System.Windows.Forms.TreeView();
    this.treeView1.set_Location(new System.Drawing.Point(72, 48));
    this.treeView1.set_Size(new System.Drawing.Size(200, 200));
    // Set the BorderStyle property to none, the BackColor property to
    // the form's backcolor, and the Scrollable property to false.  
    // This allows the TreeView to blend in form.
    this.treeView1.set_BorderStyle(BorderStyle.None);
    this.treeView1.set_BackColor(this.get_BackColor());
    this.treeView1.set_Scrollable(false);
    // Set the HideSelection property to false to keep the 
    // selection highlighted when the user leaves the control. 
    // This helps it blend with form.
    this.treeView1.set_HideSelection(false);
    // Set the ShowRootLines and ShowLines properties to false to 
    // give the TreeView a list-like appearance.
    this.treeView1.set_ShowRootLines(false);
    this.treeView1.set_ShowLines(false);
    // Add the nodes.
    this.treeView1.get_Nodes().AddRange(
        new TreeNode[] {new TreeNode("Features",
        new TreeNode[] { new TreeNode("Full Color"),
        new TreeNode("Project Wizards"),
        new TreeNode("Visual C# and Visual Basic Support") }),
        new TreeNode("System Requirements",
        new TreeNode[] {
        new TreeNode("Pentium 133 MHz or faster processor "),
        new TreeNode("Windows 98 or later"),
        new TreeNode("100 MB Disk space") }) });
    // Set the tab index and add the TreeView to the form.
    this.treeView1.set_TabIndex(0);
    this.get_Controls().Add(this.treeView1);
} //InitializeTreeView
Piattaforme

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile per Pocket PC, Windows Mobile per Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework non supporta tutte le versioni di ciascuna piattaforma. Per un elenco delle versioni supportate, vedere Requisiti di sistema.

Informazioni sulla versione

.NET Framework

Supportato in: 2.0 1.1 1.0

.NET Compact Framework

Supportato in: 2.0 1.0
Vedere anche