DrawTreeNodeEventArgs Class

 

Provides data for the DrawNode event.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

System.Object
  System.EventArgs
    System.Windows.Forms.DrawTreeNodeEventArgs

type DrawTreeNodeEventArgs = 
    class
        inherit EventArgs
    end

NameDescription
System_CAPS_pubmethodDrawTreeNodeEventArgs(Graphics, TreeNode, Rectangle, TreeNodeStates)

Initializes a new instance of the DrawTreeNodeEventArgs class.

NameDescription
System_CAPS_pubpropertyBounds

Gets the size and location of the TreeNode to draw.

System_CAPS_pubpropertyDrawDefault

Gets or sets a value indicating whether the TreeNode should be drawn by the operating system rather than being owner drawn.

System_CAPS_pubpropertyGraphics

Gets the Graphics object used to draw the TreeNode.

System_CAPS_pubpropertyNode

Gets the TreeNode to draw.

System_CAPS_pubpropertyState

Gets the current state of the TreeNode to draw.

NameDescription
System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_protmethodFinalize()

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_protmethodMemberwiseClone()

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

Use the DrawNode event to customize the appearance of nodes in a TreeView control using owner drawing.

The DrawNode event is raised by a TreeView control when its TreeView.DrawMode property is set to TreeViewDrawMode.OwnerDrawAll or TreeViewDrawMode.OwnerDrawText and a node is displayed or updated. The DrawTreeNodeEventArgs passed to the event handler contains information about the node to draw as well as providing methods to help you draw the node.

Use the State or Node properties to retrieve information about the node to draw. Use the Graphics property to do the actual drawing within the area specified by the Bounds property. To make the operating system draw a node that does not need to be owner drawn, set the DrawDefault property to true.

When the TreeView.DrawMode property is set to TreeViewDrawMode.OwnerDrawText, the area indicated by the Bounds property includes the label portion of the node only. When the TreeView.DrawMode property is set to TreeViewDrawMode.OwnerDrawAll, the Bounds area includes the entire node, including the area typically used for icons, checkboxes, plus and minus signs, and lines connecting the nodes.

The following code example demonstrates how to customize a TreeView control using owner drawing. The TreeView control in the example displays optional node tags alongside the standard node labels. Node tags are specified using the TreeNode.Tag property. The TreeView control also uses custom colors, including a custom highlight color.

You can customize most of the TreeView colors by setting color properties, but the selection highlight color is not available as a property. Additionally, the default selection highlight rectangle extends only around a node label. Owner drawing must be used to draw the node tags and to draw a customized highlight rectangle large enough to include a node tag.

In the example, a handler for the TreeView.DrawNode event draws the node tags and the custom selection highlight manually. Unselected nodes do not need customization. For these, the DrawDefault property is set to true so that they will be drawn by the operating system.

Additionally, a handler for the Control.MouseDown event provides hit-testing. By default, a node can be selected only by clicking the region around its label. The Control.MouseDown event handler selects a node that is clicked anywhere within this region or within the region around a node tag, if present.

No code example is currently available or this language may not be supported.

.NET Framework
Available since 2.0

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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