Control.CreateAccessibilityInstance Method ()

 

Creates a new accessibility object for the control.

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

Protected Overridable Function CreateAccessibilityInstance As AccessibleObject

Return Value

Type: System.Windows.Forms.AccessibleObject

A new AccessibleObject for the control.

If you do not explicitly call the CreateAccessibilityInstance method, it will be called when the AccessibilityObject property is referenced.

System_CAPS_noteNote

To get or set the AccessibilityObject property, you must add a reference to the Accessibility assembly installed with the .NET Framework.

Notes to Inheritors:

When overriding CreateAccessibilityInstance in a derived class, do not call the base class's CreateAccessibilityInstance method.

The following code example demonstrates the creation of an accessibility-aware chart control, using the AccessibleObject and Control.ControlAccessibleObject classes to expose accessible information. The control plots two curves along with a legend. The ChartControlAccessibleObject class, which derives from ControlAccessibleObject, is used in the CreateAccessibilityInstance method to provide custom accessible information for the chart control. Since the chart legend is not an actual Control -based control, but instead is drawn by the chart control, it does not any built-in accessible information. Because of this, the ChartControlAccessibleObject class overrides the GetChild method to return the CurveLegendAccessibleObject that represents accessible information for each part of the legend. When an accessible-aware application uses this control, the control can provide the necessary accessible information.

This code excerpt demonstrates overriding the CreateAccessibilityInstance method. See the AccessibleObject class overview for the complete code example.

' Overridden to return the custom AccessibleObject 
' for the entire chart.
Protected Overrides Function CreateAccessibilityInstance() As AccessibleObject
    Return New ChartControlAccessibleObject(Me)
End Function 

.NET Framework
Available since 1.1
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