VisualTreeHelper Class

Definition

public ref class VisualTreeHelper abstract sealed

public static class VisualTreeHelper

type VisualTreeHelper = class

Public Class VisualTreeHelper

Inheritance

Object

VisualTreeHelper

Examples

The following example shows how to enumerate all the descendants of a visual object, which is a technique you might want to use if you were interested in serializing all the rendering information of a visual object hierarchy.

// Enumerate all the descendants of the visual object.
public static void EnumVisual(Visual myVisual)
{
    for (int i = 0; i < VisualTreeHelper.GetChildrenCount(myVisual); i++)
    {
        // Retrieve child visual at specified index value.
        Visual childVisual = (Visual)VisualTreeHelper.GetChild(myVisual, i);

        // Do processing of the child visual object.

        // Enumerate children of the child visual object.
        EnumVisual(childVisual);
    }
}

' Enumerate all the descendants of the visual object.
Public Shared Sub EnumVisual(ByVal myVisual As Visual)
    For i As Integer = 0 To VisualTreeHelper.GetChildrenCount(myVisual) - 1
        ' Retrieve child visual at specified index value.
        Dim childVisual As Visual = CType(VisualTreeHelper.GetChild(myVisual, i), Visual)

        ' Do processing of the child visual object.

        ' Enumerate children of the child visual object.
        EnumVisual(childVisual)
    Next i
End Sub

Remarks

Nodes in the visual tree can be either Visual or Visual3D objects. Methods that are specific to a type of visual object are typed as either Visual or Visual3D. However, some methods in the VisualTreeHelper class can accept a DependencyObject value that represents either type of visual object.

WPF supports programmatic access to several different tree structures of objects. Primarily, this is exposed as a visual tree and a logical tree. In some cases, the logical tree is a more useful representation of the elements in a WPF application, but conceptually the logical tree is implemented at a level beyond the Visual class. Unlike the visual tree, the logical tree can represent nonvisual data objects, such as ListItem. For more information on the logical tree, see Trees in WPF. The logical tree also is supported by a similar utility method class, LogicalTreeHelper.

Methods

Applies to