استخدام تخزين مؤقت في واجه المستخدم التنفيذ التلقائي

ملاحظة
Th هو الوثائق هو المقصودة لإطار عمل.NET المطورين الذين يرغبون في استخدام المدارة UI Automationالفئات المعرفة في System.Windows.Automationمساحة الاسم.للحصول على أحدث المعلومات حول UI Automation، راجع API التنفيذ التلقائي Windows: أتمتة واجه المستخدم.

يظهر هذا المقطع كيفية إلى تنفيذ تخزين مؤقت من AutomationElementالخصائص و أنماط التحكم .

تنشيط طلب ذاكرة تخزين مؤقت

1. قم بإنشاء CacheRequest

2. تعيين خصائص و أنماط إلى ذاكرة تخزين مؤقت باستخدام Add.

3. تعيين نطاق ذاكرة تخزين مؤقت بواسطة إعداد TreeScopeخاصية.

4. قم بتحديد طريقة عرض شجرة فرعية بواسطة تعيين TreeFilterخاصية.

5. قم بتعيين AutomationElementModeخاصية إلى Noneإذا كنت ترغب في زيادة فعالية بواسطة غير استرداد مرجع كامل للكائنات. (يؤدي هذا إلى جعل من المستحيل إلى استرداد قيم الحالي من هذه الكائنات.)

6. تنشيط طلب باستخدام Activateداخل usingكتلة ( Usingفي Microsoft Visual Basic .NET).

بعد الحصول على AutomationElementالكائنات أو الاشتراك في إلى الأحداث، إلغاء تنشيط الطلب باستخدام Pop(ifPushwas used) أو بترتيبها الكائن الذي يتم إنشاؤه بواسطة Activate. (استخدمActivateفي ausingحظر (UsingفيMicrosoft Visual Basic .NET).

خصائص AutomationElement ذاكرة تخزين مؤقت

1. بينما CacheRequestنشطاً، الحصول على AutomationElementالكائنات بواسطة استخدام FindFirstأو FindAll؛ أو الحصول على AutomationElementكمصدر لحدث مسجَّل وقت CacheRequestتم نشطة. (يمكنك أيضا إنشاء ذاكرة تخزين مؤقت بتمرير CacheRequestGetUpdatedCache أو واحد TreeWalkerالأساليب.)

2. استخدام GetCachedPropertyValueأو استرداد خاصية من Cachedخاصية AutomationElement.

الحصول على نقش المخزنة مؤقتاً والخصائص الخاصة بها

1. بينما CacheRequestنشطاً، الحصول على AutomationElementالكائنات بواسطة استخدام FindFirstأو FindAll؛ أو الحصول على AutomationElementكمصدر لحدث مسجَّل وقت CacheRequestتم نشطة. (يمكنك أيضا إنشاء ذاكرة تخزين مؤقت بتمرير CacheRequestGetUpdatedCache أو واحد TreeWalkerالأساليب.)

2. استخدام GetCachedPatternأو TryGetCachedPatternإلى استرداد نقش المخزنة مؤقتاً.

3. استرداد قيم الخصائص من Cachedخاصية عنصر تحكم نقش.

مثال

يلي تعليمات برمجية يظهر المثال بالأوجه المختلفة للتخزين المؤقت، وذلك باستخدام Activateلتنشيط CacheRequest.

    ''' <summary>
    ''' Caches and retrieves properties for a list item by using CacheRequest.Activate.
    ''' </summary>
    ''' <param name="elementList">Element from which to retrieve a child element.</param>
    ''' <remarks>
    ''' This code demonstrates various aspects of caching. It is not intended to be 
    ''' an example of a useful method.
    ''' </remarks>
    Private Sub CachePropertiesByActivate(ByVal elementList As AutomationElement)

        ' Set up the request.
        Dim myCacheRequest As New CacheRequest()
        myCacheRequest.Add(AutomationElement.NameProperty)
        myCacheRequest.Add(AutomationElement.IsEnabledProperty)
        myCacheRequest.Add(SelectionItemPattern.Pattern)
        myCacheRequest.Add(SelectionItemPattern.SelectionContainerProperty)

        Dim elementListItem As AutomationElement

        ' Obtain an element and cache the requested items.
        Using myCacheRequest.Activate()
            Dim myCondition As New PropertyCondition( _
                AutomationElement.IsSelectionItemPatternAvailableProperty, True)
            elementListItem = elementList.FindFirst(TreeScope.Children, myCondition)
        End Using


        ' The CacheRequest is now inactive.
        ' Retrieve the cached property and pattern.
        Dim pattern As SelectionItemPattern
        Dim itemName As String
        Try
            itemName = elementListItem.Cached.Name
            pattern = DirectCast(elementListItem.GetCachedPattern(SelectionItemPattern.Pattern), _
                SelectionItemPattern)
        Catch ex As InvalidOperationException
            Console.WriteLine("Object was not in cache.")
            Return
        End Try
        ' Alternatively, you can use TryGetCachedPattern to retrieve the cached pattern.
        Dim cachedPattern As Object = Nothing
        If True = elementListItem.TryGetCachedPattern(SelectionItemPattern.Pattern, cachedPattern) Then
            pattern = DirectCast(cachedPattern, SelectionItemPattern)
        End If

        ' Specified pattern properties are also in the cache.
        Dim parentList As AutomationElement = pattern.Cached.SelectionContainer

        ' The following line will raise an exception, because the HelpText property was not cached.
        '** String itemHelp = elementListItem.Cached.HelpText; **

        ' Similarly, pattern properties that were not specified in the CacheRequest cannot be 
        ' retrieved from the cache. This would raise an exception.
        '** bool selected = pattern.Cached.IsSelected; **

        ' This is still a valid call, even though the property is in the cache.
        ' Of course, the cached value and the current value are not guaranteed to be the same.
        itemName = elementListItem.Current.Name
    End Sub 'CachePropertiesByActivate

/// <summary>
/// Caches and retrieves properties for a list item by using CacheRequest.Activate.
/// </summary>
/// <param name="elementList">Element from which to retrieve a child element.</param>
/// <remarks>
/// This code demonstrates various aspects of caching. It is not intended to be 
/// an example of a useful method.
/// </remarks>
private void CachePropertiesByActivate(AutomationElement elementList)
{
    AutomationElement elementListItem;

    // Set up the request.
    CacheRequest cacheRequest = new CacheRequest();
    cacheRequest.Add(AutomationElement.NameProperty);
    cacheRequest.Add(AutomationElement.IsEnabledProperty);
    cacheRequest.Add(SelectionItemPattern.Pattern);
    cacheRequest.Add(SelectionItemPattern.SelectionContainerProperty);

    // Obtain an element and cache the requested items.
    using (cacheRequest.Activate())
    {
        Condition cond = new PropertyCondition(AutomationElement.IsSelectionItemPatternAvailableProperty, true);
        elementListItem = elementList.FindFirst(TreeScope.Children, cond);
    }
    // The CacheRequest is now inactive.

    // Retrieve the cached property and pattern.
    SelectionItemPattern pattern;
    String itemName;
    try
    {
        itemName = elementListItem.Cached.Name;
        pattern = elementListItem.GetCachedPattern(SelectionItemPattern.Pattern) as SelectionItemPattern;
    }
    catch (InvalidOperationException)
    {
        Console.WriteLine("Object was not in cache.");
        return;
    }
    // Alternatively, you can use TryGetCachedPattern to retrieve the cached pattern.
    object cachedPattern;
    if (true == elementListItem.TryGetCachedPattern(SelectionItemPattern.Pattern, out cachedPattern))
    {
        pattern = cachedPattern as SelectionItemPattern;
    }

    // Specified pattern properties are also in the cache.
    AutomationElement parentList = pattern.Cached.SelectionContainer;

    // The following line will raise an exception, because the HelpText property was not cached.
    /*** String itemHelp = elementListItem.Cached.HelpText; ***/

    // Similarly, pattern properties that were not specified in the CacheRequest cannot be 
    // retrieved from the cache. This would raise an exception.
    /*** bool selected = pattern.Cached.IsSelected; ***/

    // This is still a valid call, even though the property is in the cache.
    // Of course, the cached value and the current value are not guaranteed to be the same.
    itemName = elementListItem.Current.Name;
}

يلي تعليمات برمجية يظهر المثال بالأوجه المختلفة للتخزين المؤقت، وذلك باستخدام Pushلتنشيط CacheRequest. باستثناء طلبات wهوh لتضمين ذاكرة تخزين مؤقت، فإنه هو المفضل لاستخدام Activate.

''' <summary>
''' Caches and retrieves properties for a list item by using CacheRequest.Push.
''' </summary>
''' <param name="elementList">Element from which to retrieve a child element.</param>
''' <remarks>
''' This code demonstrates various aspects of caching. It is not intended to be 
''' an example of a useful method.
''' </remarks>
Private Sub CachePropertiesByPush(ByVal elementList As AutomationElement)
    ' Set up the request.
    Dim cacheRequest As New CacheRequest()

    ' Do not get a full reference to the cached objects, only to their cached properties and patterns.
    cacheRequest.AutomationElementMode = AutomationElementMode.None

    ' Cache all elements, regardless of whether they are control or content elements.
    cacheRequest.TreeFilter = Automation.RawViewCondition

    ' Property and pattern to cache.
    cacheRequest.Add(AutomationElement.NameProperty)
    cacheRequest.Add(SelectionItemPattern.Pattern)

    ' Activate the request.
    cacheRequest.Push()

    ' Obtain an element and cache the requested items.
    Dim myCondition As New PropertyCondition(AutomationElement.IsSelectionItemPatternAvailableProperty, _
        True)
    Dim elementListItem As AutomationElement = elementList.FindFirst(TreeScope.Children, myCondition)

    ' At this point, you could call another method that creates a CacheRequest and calls Push/Pop.
    ' While that method was retrieving automation elements, the CacheRequest set in this method 
    ' would not be active. 
    ' Deactivate the request.
    cacheRequest.Pop()

    ' Retrieve the cached property and pattern.
    Dim itemName As String = elementListItem.Cached.Name
    Dim pattern As SelectionItemPattern = _
        DirectCast(elementListItem.GetCachedPattern(SelectionItemPattern.Pattern), SelectionItemPattern)

    ' The following is an alternative way of retrieving the Name property.
    itemName = CStr(elementListItem.GetCachedPropertyValue(AutomationElement.NameProperty))

    ' This is yet another way, which returns AutomationElement.NotSupported if the element does
    ' not supply a value. If the second parameter is false, a default name is returned.
    Dim objName As Object = elementListItem.GetCachedPropertyValue(AutomationElement.NameProperty, True)
    If objName Is AutomationElement.NotSupported Then
        itemName = "Unknown"
    Else
        itemName = CStr(objName)
    End If
    ' The following call raises an exception, because only the cached properties are available, 
    '  as specified by cacheRequest.AutomationElementMode. If AutomationElementMode had its
    '  default value (Full), this call would be valid.
    '** bool enabled = elementListItem.Current.IsEnabled; **

End Sub 'CachePropertiesByPush

/// <summary>
/// Caches and retrieves properties for a list item by using CacheRequest.Push.
/// </summary>
/// <param name="autoElement">Element from which to retrieve a child element.</param>
/// <remarks>
/// This code demonstrates various aspects of caching. It is not intended to be 
/// an example of a useful method.
/// </remarks>
private void CachePropertiesByPush(AutomationElement elementList)
{
    // Set up the request.
    CacheRequest cacheRequest = new CacheRequest();

    // Do not get a full reference to the cached objects, only to their cached properties and patterns.
    cacheRequest.AutomationElementMode = AutomationElementMode.None;

    // Cache all elements, regardless of whether they are control or content elements.
    cacheRequest.TreeFilter = Automation.RawViewCondition;

    // Property and pattern to cache.
    cacheRequest.Add(AutomationElement.NameProperty);
    cacheRequest.Add(SelectionItemPattern.Pattern);

    // Activate the request.
    cacheRequest.Push();

    // Obtain an element and cache the requested items.
    Condition cond = new PropertyCondition(AutomationElement.IsSelectionItemPatternAvailableProperty, true);
    AutomationElement elementListItem = elementList.FindFirst(TreeScope.Children, cond);

    // At this point, you could call another method that creates a CacheRequest and calls Push/Pop.
    // While that method was retrieving automation elements, the CacheRequest set in this method 
    // would not be active. 

    // Deactivate the request.
    cacheRequest.Pop();

    // Retrieve the cached property and pattern.
    String itemName = elementListItem.Cached.Name;
    SelectionItemPattern pattern = elementListItem.GetCachedPattern(SelectionItemPattern.Pattern) as SelectionItemPattern;

    // The following is an alternative way of retrieving the Name property.
    itemName = elementListItem.GetCachedPropertyValue(AutomationElement.NameProperty) as String;

    // This is yet another way, which returns AutomationElement.NotSupported if the element does
    // not supply a value. If the second parameter is false, a default name is returned.
    object objName = elementListItem.GetCachedPropertyValue(AutomationElement.NameProperty, true);
    if (objName == AutomationElement.NotSupported)
    {
        itemName = "Unknown";
    }
    else
    {
        itemName = objName as String;
    }

    // The following call raises an exception, because only the cached properties are available, 
    //  as specified by cacheRequest.AutomationElementMode. If AutomationElementMode had its
    //  default value (Full), this call would be valid.
    /*** bool enabled = elementListItem.Current.IsEnabled; ***/
}

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المبادئ

تخزين مؤقت في التنفيذ التلقائي واجه المستخدم العملاء