Return Properties from a UI Automation Provider

Note

This documentation is intended for .NET Framework developers who want to use the managed UI Automation classes defined in the System.Windows.Automation namespace. For the latest information about UI Automation, see Windows Automation API: UI Automation.

This topic contains sample code that shows how a UI Automation provider can return properties of an element to client applications.

For any property it does not explicitly support, the provider must return null (Nothing in Visual Basic). This ensures that UI Automation attempts to obtain the property from another source, such as the host window provider.

Example

/// <summary>
/// Gets provider property values.
/// </summary>
/// <param name="propId">Property identifier.</param>
/// <returns>The value of the property.</returns>
object IRawElementProviderSimple.GetPropertyValue(int propId)
{
    if (propId == AutomationElementIdentifiers.NameProperty.Id)
    {
        return "Custom list control";
    }
    else if (propId == AutomationElementIdentifiers.ControlTypeProperty.Id)
    {
        return ControlType.List.Id;  
    }
    else if (propId == AutomationElementIdentifiers.IsContentElementProperty.Id)
    {
        return true;
    }
    else if (propId == AutomationElementIdentifiers.IsControlElementProperty.Id)
    {
        return true;
    }
    else
    {
        return null;
    }
}
''' <summary>
''' Gets provider property values.
''' </summary>
''' <param name="propId">Property identifier.</param>
''' <returns>The value of the property.</returns>
Function GetPropertyValue(ByVal propId As Integer) As Object _
    Implements IRawElementProviderSimple.GetPropertyValue

    If propId = AutomationElementIdentifiers.NameProperty.Id Then
        Return "Custom list control"
    ElseIf propId = AutomationElementIdentifiers.ControlTypeProperty.Id Then
        Return ControlType.List.Id
    ElseIf propId = AutomationElementIdentifiers.IsContentElementProperty.Id Then
        Return True
    ElseIf propId = AutomationElementIdentifiers.IsControlElementProperty.Id Then
        Return True
    Else
        Return Nothing
    End If
End Function 'IRawElementProviderSimple.GetPropertyValue

See Also

UI Automation Providers Overview
Server-Side UI Automation Provider Implementation