TreeViewEventArgs Class
Provides data for the AfterCheck, AfterCollapse, AfterExpand, or AfterSelect events of a TreeView control.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
| Name | Description | |
|---|---|---|
![]() | TreeViewEventArgs(TreeNode^) | Initializes a new instance of the TreeViewEventArgs class for the specified tree node. |
![]() | TreeViewEventArgs(TreeNode^, TreeViewAction) | Initializes a new instance of the TreeViewEventArgs class for the specified tree node and with the specified type of action that raised the event. |
| Name | Description | |
|---|---|---|
![]() | Equals(Object^) | Determines whether the specified object is equal to the current object.(Inherited from Object.) |
![]() | Finalize() | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.) |
![]() | GetHashCode() | Serves as the default hash function. (Inherited from Object.) |
![]() | GetType() | |
![]() | MemberwiseClone() | |
![]() | ToString() | Returns a string that represents the current object.(Inherited from Object.) |
For more information about handling events, see Handling and Raising Events.
The following example illustrates a customized TreeView. By inheriting the TreeView class, this custom version has all the functionality of a normal TreeView. Changing various property values in the constructor provides a unique appearance. Because the ShowPlusMinus property is set to false, the customized control also overrides the OnAfterSelect method so nodes can be expanded and collapsed when they are clicked.
A control that is customized in this way can be used throughout an organization, making it easy to provide a consistent interface without requiring the control properties to be specified in each individual project.
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; } };
Available since 1.1
Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.


