TreeView.Indent 属性

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

获取或设置每个子树节点级别的缩进距离。

public:
 property int Indent { int get(); void set(int value); };

public int Indent { get; set; }

member this.Indent : int with get, set

Public Property Indent As Integer

属性值

Int32

每个子树节点级别的缩进距离（以像素为单位）。 默认值为 19。

例外

ArgumentOutOfRangeException

所分配的值小于 0。

- 或 -

分配的值大于 32,000。

示例

下面的代码示例演示了自定义 TreeView的 。 通过继承 TreeView 类，此自定义版本具有典型 TreeView的所有功能。 更改构造函数中的各种属性值可提供独特的外观。 由于 属性 ShowPlusMinus 设置为 false，因此自定义控件还会重写 OnAfterSelect 方法，以便在单击节点时可以展开和折叠节点。

以这种方式自定义的控件可以在整个组织中使用，这样就可以轻松地提供一致的界面，而无需在每个单独的项目中指定控件属性。

public ref class CustomizedTreeView: public TreeView
{
public:
   CustomizedTreeView()
   {

      // Customize the TreeView control by setting various properties.
      BackColor = System::Drawing::Color::CadetBlue;
      FullRowSelect = true;
      HotTracking = true;
      Indent = 34;
      ShowPlusMinus = false;

      // The ShowLines property must be false for the FullRowSelect
      // property to work.
      ShowLines = false;
   }

protected:
   virtual void OnAfterSelect( TreeViewEventArgs^ e ) override
   {
      // Confirm that the user initiated the selection.
      // This prevents the first node from expanding when it is
      // automatically selected during the initialization of
      // the TreeView control.
      if ( e->Action != TreeViewAction::Unknown )
      {
         if ( e->Node->IsExpanded )
         {
            e->Node->Collapse();
         }
         else
         {
            e->Node->Expand();
         }
      }

      
      // Remove the selection. This allows the same node to be
      // clicked twice in succession to toggle the expansion state.
      SelectedNode = nullptr;
   }
};

public class CustomizedTreeView : TreeView
{
    public CustomizedTreeView()
    {
        // Customize the TreeView control by setting various properties.
        BackColor = System.Drawing.Color.CadetBlue;
        FullRowSelect = true;
        HotTracking = true;
        Indent = 34;
        ShowPlusMinus = false;

        // The ShowLines property must be false for the FullRowSelect 
        // property to work.
        ShowLines = false;
    }

    protected override void OnAfterSelect(TreeViewEventArgs e)
    {
        // Confirm that the user initiated the selection.
        // This prevents the first node from expanding when it is
        // automatically selected during the initialization of 
        // the TreeView control.
        if (e.Action != TreeViewAction.Unknown)
        {
            if (e.Node.IsExpanded) 
            {
                e.Node.Collapse();
            }
            else 
            {
                e.Node.Expand();
            }
        }

        // Remove the selection. This allows the same node to be
        // clicked twice in succession to toggle the expansion state.
        SelectedNode = null;
    }
}

Public Class CustomizedTreeView
    Inherits TreeView

    Public Sub New()
        ' Customize the TreeView control by setting various properties.
        BackColor = System.Drawing.Color.CadetBlue
        FullRowSelect = True
        HotTracking = True
        Indent = 34
        ShowPlusMinus = False

        ' The ShowLines property must be false for the FullRowSelect 
        ' property to work.
        ShowLines = False
    End Sub


    Protected Overrides Sub OnAfterSelect(ByVal e As TreeViewEventArgs)
        ' Confirm that the user initiated the selection.
        ' This prevents the first node from expanding when it is
        ' automatically selected during the initialization of 
        ' the TreeView control.
        If e.Action <> TreeViewAction.Unknown Then
            If e.Node.IsExpanded Then
                e.Node.Collapse()
            Else
                e.Node.Expand()
            End If
        End If

        ' Remove the selection. This allows the same node to be
        ' clicked twice in succession to toggle the expansion state.
        SelectedNode = Nothing
    End Sub

End Class

注解

如果将此属性设置为值 -1，则该值尚未从其默认值更改，则不会引发异常。 这是因为控件在创建控件句柄之前使用值 -1 作为内部默认值。 此内部默认值会导致包装控件返回其自己的默认值 19。