Επεξεργασία

Κοινή χρήση μέσω

AutomationProperty Class

  • Reference

Definition

Namespace:
System.Windows.Automation
Assembly:
UIAutomationTypes.dll

Identifies a property of an AutomationElement.

public ref class AutomationProperty : System::Windows::Automation::AutomationIdentifier
public class AutomationProperty : System.Windows.Automation.AutomationIdentifier
type AutomationProperty = class
    inherit AutomationIdentifier
Public Class AutomationProperty
Inherits AutomationIdentifier
Inheritance
Object
AutomationIdentifier
AutomationProperty

Examples

The following example adds a property-changed event handler, and the handler checks the Property member of the event arguments to determine the property that has been changed.


AutomationPropertyChangedEventHandler propChangeHandler;
/// <summary>
/// Adds a handler for property-changed event; in particular, a change in the enabled state.
/// </summary>
/// <param name="element">The UI Automation element whose state is being monitored.</param>
public void SubscribePropertyChange(AutomationElement element)
{
    Automation.AddAutomationPropertyChangedEventHandler(element, 
        TreeScope.Element, 
        propChangeHandler = new AutomationPropertyChangedEventHandler(OnPropertyChange),
        AutomationElement.IsEnabledProperty);
}

/// <summary>
/// Handler for property changes.
/// </summary>
/// <param name="src">The source whose properties changed.</param>
/// <param name="e">Event arguments.</param>
private void OnPropertyChange(object src, AutomationPropertyChangedEventArgs e)
{
    AutomationElement sourceElement = src as AutomationElement;
    if (e.Property == AutomationElement.IsEnabledProperty)
    {
        bool enabled = (bool)e.NewValue;
        // TODO: Do something with the new value. 
        // The element that raised the event can be identified by its runtime ID property.
    }
    else
    { 
        // TODO: Handle other property-changed events.
    }
}

public void UnsubscribePropertyChange(AutomationElement element)
{
    if (propChangeHandler != null)
    {
        Automation.RemoveAutomationPropertyChangedEventHandler(element, propChangeHandler);
    }
}


Dim propChangeHandler As AutomationPropertyChangedEventHandler

''' <summary>
''' Adds a handler for property-changed event; in particular, a change in the enabled state.
''' </summary>
''' <param name="element">The UI Automation element whose state is being monitored.</param>
Public Sub SubscribePropertyChange(ByVal element As AutomationElement)
    propChangeHandler = _
        New AutomationPropertyChangedEventHandler(AddressOf OnPropertyChange)
    Automation.AddAutomationPropertyChangedEventHandler(element, TreeScope.Element, _
        propChangeHandler, AutomationElement.IsEnabledProperty)

End Sub



''' <summary>
''' Handler for property changes.
''' </summary>
''' <param name="src">The source whose properties changed.</param>
''' <param name="e">Event arguments.</param>
Private Sub OnPropertyChange(ByVal src As Object, ByVal e As AutomationPropertyChangedEventArgs) 
    Dim sourceElement As AutomationElement = DirectCast(src, AutomationElement)
    If e.Property Is AutomationElement.IsEnabledProperty Then
        Dim enabled As Boolean = CBool(e.NewValue)
        ' TODO: Do something with the new value. 
        ' The element that raised the event can be identified by its runtime ID property.
    Else
    End If
 ' TODO: Handle other property-changed events.
End Sub


Public Sub UnsubscribePropertyChange(ByVal element As AutomationElement)
    If (propChangeHandler IsNot Nothing) Then
        Automation.RemoveAutomationPropertyChangedEventHandler(element, propChangeHandler)
    End If

End Sub

Remarks

This class identifies properties, not the values of properties. Static objects of this type are found as fields of AutomationElement and control pattern classes.

Properties

Id

Gets the underlying numerical identifier.

(Inherited from AutomationIdentifier)
ProgrammaticName

Gets the registered programmatic name.

(Inherited from AutomationIdentifier)

Methods

CompareTo(Object)

Compares this AutomationIdentifier with another AutomationIdentifier.

(Inherited from AutomationIdentifier)
Equals(Object)

Returns a value indicating whether the supplied AutomationIdentifier is equivalent to this AutomationIdentifier.

(Inherited from AutomationIdentifier)
GetHashCode()

Returns the hash code for this UI Automation identifier.

(Inherited from AutomationIdentifier)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
LookupById(Int32)

Retrieves an AutomationProperty that encapsulates a specified numerical identifier.
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also