TreeView.GetNodeCount 方法

检索分配给树视图控件的树节点数（可以选择性地包括所有子树中的树节点）。

**命名空间:**System.Windows.Forms
**程序集:**System.Windows.Forms（在 system.windows.forms.dll 中）

语法

声明
Public Function GetNodeCount ( _
    includeSubTrees As Boolean _
) As Integer
用法
Dim instance As TreeView
Dim includeSubTrees As Boolean
Dim returnValue As Integer

returnValue = instance.GetNodeCount(includeSubTrees)

public int GetNodeCount (
    bool includeSubTrees
)

public:
int GetNodeCount (
    bool includeSubTrees
)

public int GetNodeCount (
    boolean includeSubTrees
)

public function GetNodeCount (
    includeSubTrees : boolean
) : int

参数

• includeSubTrees
  如果计入子树包含的 TreeNode 项，则为 true；否则为 false。

返回值

分配给树视图控件的树节点数（可以选择性地包括所有子树中的树节点）。

备注

如果 includeSubTrees 为 true，所得结果为整个树结构中所有树节点的总数。

示例

下面的代码示例设置 TreeView 的 PathSeparator 属性，并显示 SelectedNode 的 TreeNodeCollection 中包含的子树节点数。还显示树视图控件中子树节点占全部树节点的百分比。本示例要求有一个包含 Button 的 Form 和一个包含 TreeNodeCollection 的 TreeView 控件，该集合包含若干个（最好是具有三级或三级以上的）TreeNode 对象。

Private Sub myButton_Click(ByVal sender As Object, _
  ByVal e As System.EventArgs) Handles myButton.Click
   ' Set the tre view's PathSeparator property.
   myTreeView.PathSeparator = "."

   ' Get the count of the child tree nodes contained in the SelectedNode.
   Dim myNodeCount As Integer = myTreeView.SelectedNode.GetNodeCount(True)
   Dim myChildPercentage As Decimal = CDec(myNodeCount) / _
      CDec(myTreeView.GetNodeCount(True)) * 100

   ' Display the tree node path and the number of child nodes it and the tree view have.
   MessageBox.Show(("The '" + myTreeView.SelectedNode.FullPath + "' node has " _
      + myNodeCount.ToString() + " child nodes." + Microsoft.VisualBasic.ControlChars.Lf _
      + "That is " + String.Format("{0:###.##}", myChildPercentage) _
      + "% of the total tree nodes in the tree view control."))
End Sub

private void myButton_Click(object sender, System.EventArgs e)
{
   // Set the tre view's PathSeparator property.
   myTreeView.PathSeparator = ".";

   // Get the count of the child tree nodes contained in the SelectedNode.
   int myNodeCount = myTreeView.SelectedNode.GetNodeCount(true);
   decimal myChildPercentage = ((decimal)myNodeCount/
     (decimal)myTreeView.GetNodeCount(true)) * 100;

   // Display the tree node path and the number of child nodes it and the tree view have.
   MessageBox.Show("The '" + myTreeView.SelectedNode.FullPath + "' node has " 
     + myNodeCount.ToString() + " child nodes.\nThat is " 
     + string.Format("{0:###.##}", myChildPercentage) 
     + "% of the total tree nodes in the tree view control.");
}

void myButton_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   
   // Set the tre view's PathSeparator property.
   myTreeView->PathSeparator = ".";
   
   // Get the count of the child tree nodes contained in the SelectedNode.
   int myNodeCount = myTreeView->SelectedNode->GetNodeCount( true );
   Decimal myChildPercentage = ((Decimal)myNodeCount / (Decimal)myTreeView->GetNodeCount( true )) * 100;
   
   // Display the tree node path and the number of child nodes it and the tree view have.
   MessageBox::Show( String::Concat( "The '", myTreeView->SelectedNode->FullPath, "' node has ", myNodeCount, " child nodes.\nThat is ", String::Format( "{0:###.##}", myChildPercentage ), "% of the total tree nodes in the tree view control." ) );
}

private void myButton_Click(Object sender, System.EventArgs e)
{
    // Set the tre view's PathSeparator property.
    myTreeView.set_PathSeparator(".");
    // Get the count of the child tree nodes contained in the SelectedNode.
    int myNodeCount = myTreeView.get_SelectedNode().GetNodeCount(true);
    System.Decimal myChildPercentage =
        Decimal.Multiply(Decimal.Divide(new Decimal(myNodeCount),
        new Decimal(myTreeView.GetNodeCount(true))), new Decimal(100));
    // Display the tree node path and the number of child nodes it and the
    // tree view have.
    MessageBox.Show("The '" + myTreeView.get_SelectedNode().get_FullPath()
        + "' node has " + ((Int32)myNodeCount).ToString()
        + " child nodes.\nThat is " + String.Format("{0:###.##}",
        myChildPercentage)
        + "% of the total tree nodes in the tree view control.");
} //myButton_Click

平台

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

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。

版本信息

.NET Framework

受以下版本支持：2.0、1.1、1.0

.NET Compact Framework

受以下版本支持：2.0、1.0

请参见

参考

TreeView 类
TreeView 成员
System.Windows.Forms 命名空间
TreeNode 类