TreeView.ShowRootLines 属性

定义

获取或设置一个值,用以指示是否在树视图根处的树节点之间绘制连线。Gets or sets a value indicating whether lines are drawn between the tree nodes that are at the root of the tree view.

public:
 property bool ShowRootLines { bool get(); void set(bool value); };
public bool ShowRootLines { get; set; }
member this.ShowRootLines : bool with get, set
Public Property ShowRootLines As Boolean

属性值

Boolean

如果在树视图根处的树节点之间绘制连线,则为 true;否则为 falsetrue if lines are drawn between the tree nodes that are at the root of the tree view; otherwise, false. 默认值为 trueThe default is true.

示例

下面的代码示例演示如何使用 BorderStyle 枚举以及 BorderStyle 、、 ShowLines Scrollable HideSelectionShowRootLines 属性。The following code example demonstrates how to use the BorderStyle enumeration and the BorderStyle, ShowLines, Scrollable, HideSelection and ShowRootLines properties. 若要运行此示例,请将以下代码粘贴到窗体中,并 InitializeTreeView 在窗体的构造函数或方法中调用方法 LoadTo run this example, paste the following code in a form and call the InitializeTreeView method in the form's constructor or Load method.

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

private:
   // Initialize the TreeView to blend with the form, giving it the 
   // same color as the form and no border.
   void InitializeTreeView()
   {
      // Create a new TreeView control and set the location and size.
      this->TreeView1 = gcnew System::Windows::Forms::TreeView;
      this->TreeView1->Location = System::Drawing::Point( 72, 48 );
      this->TreeView1->Size = 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.
      array<TreeNode^>^temp0 = {gcnew TreeNode( "Full Color" ),gcnew TreeNode( "Project Wizards" ),gcnew TreeNode( "Visual C# and Visual Basic Support" )};
      array<TreeNode^>^temp1 = {gcnew TreeNode( "Pentium 133 MHz or faster processor " ),gcnew TreeNode( "Windows 98 or later" ),gcnew TreeNode( "100 MB Disk space" )};
      array<TreeNode^>^temp2 = {gcnew TreeNode( "Features",temp0 ),gcnew TreeNode( "System Requirements",temp1 )};
      this->TreeView1->Nodes->AddRange( temp2 );

      // Set the tab index and add the TreeView to the form.
      this->TreeView1->TabIndex = 0;
      this->Controls->Add( this->TreeView1 );
   }

// 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);
}

' 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

注解

如果 ShowRootLines 属性为 false ,则不会在根树节点旁显示加号和减号按钮,并且 ShowPlusMinus 属性将不起作用。If the ShowRootLines property is false, the plus-sign and minus-sign buttons will not appear next to the root tree nodes, and the ShowPlusMinus property will have no effect.

适用于

另请参阅