Code:
/ Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / Orcas / QFE / wpf / src / UIAutomation / UIAutomationClient / System / Windows / Automation / CacheRequest.cs / 1 / CacheRequest.cs
//----------------------------------------------------------------------------
//
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//
//
// Description: Class that describes the data to be pre-fected in Automation
// element operations, and manange the current request.
//
// History:
// 02/05/2004 : BrendanM Ported to WCP
//
//---------------------------------------------------------------------------
using System;
using System.Collections;
using System.Diagnostics;
using System.Windows.Automation;
using MS.Internal.Automation;
namespace System.Windows.Automation
{
///
/// Specified type of reference to use when returning AutomationElements
///
///
/// AutomationElementMode.Full is the default, and specified that returned AutomationElements
/// contain a full reference to the underlying UI.
///
/// AutomationElementMode.None specifies taht the returned AutomationElements have no
/// reference to the underlying UI, and contain only cached information.
///
/// Certain operations on AutomationElements, such as GetCurrentProperty
/// or SetFocus require a full reference; attempting to perform these on an
/// AutomationElement that has AutomationElementMode.None will result in an
/// InvalidOperationException being thrown.
///
/// Using AutomationElementMode.None can be more efficient when only properties are needed,
/// as it avoids the overhead involved in setting up full references.
///
#if (INTERNAL_COMPILE)
internal enum AutomationElementMode
#else
public enum AutomationElementMode
#endif
{
///
/// Specifies that returned AutomationElements have no reference to the
/// underlying UI, and contain only cached information.
///
None,
///
/// Specifies that returned AutomationElements have a full reference to the
/// underlying UI.
///
Full
}
// Implementation notes:
//
// CacheRequest is the user-facing class that is used to build up
// cache requests, using Add and the other properties. When activated,
// the data is gathered into a UiaCacheRequest instance, which is
// immutable - these are what the rest of UIA uses internally.
//
// The default cache request - which appears to be always at the bottom
// of the stack and which cannot be moved - is not actually part of the
// stack. Instead, current returns it whever the stack is empty.
///
/// Class used to specify the properties and patterns that should be
/// prefetched by UIAutomation when returning AutomationElements.
///
#if (INTERNAL_COMPILE)
internal sealed class CacheRequest
#else
public sealed class CacheRequest
#endif
{
//-----------------------------------------------------
//
// Constructors
//
//-----------------------------------------------------
#region Constructors
///
/// Create a new CacheRequest with default values.
///
///
/// A Thread's current CacheRequest determins which properties,
/// patterns and relative elements - if any - are pre-fetched by
/// AutomationElement.
///
/// A default cache request works on the Control view of the tree,
/// and does not prefetch any properties or patterns.
///
/// Use .Push or .Activate to make the CacheRequest the current active
/// CacheRequest for the current thread.
///
public CacheRequest()
{
_instanceLock = new object();
_viewCondition = Automation.ControlViewCondition;
_scope = TreeScope.Element;
_properties = new ArrayList();
_patterns = new ArrayList();
_automationElementMode = AutomationElementMode.Full;
// We always want RuntimeID to be available...
_properties.Add(AutomationElement.RuntimeIdProperty);
_uiaCacheRequest = DefaultUiaCacheRequest;
}
// Private ctor used by Clone()
private CacheRequest( Condition viewCondition,
TreeScope scope,
ArrayList properties,
ArrayList patterns,
AutomationElementMode automationElementMode,
UiaCoreApi.UiaCacheRequest uiaCacheRequest)
{
_instanceLock = new object();
_viewCondition = viewCondition;
_scope = scope;
_properties = properties;
_patterns = patterns;
_automationElementMode = automationElementMode;
_uiaCacheRequest = uiaCacheRequest;
}
#endregion Constructors
//------------------------------------------------------
//
// Public Methods
//
//-----------------------------------------------------
#region Public Methods
///
/// Push this CacheRequest onto this thread's stack of CacheRequests,
/// making it the current CacheRequest for this thread.
///
///
/// Use Pop to remove this CacheRequest from the stack, making the previously
/// active CacheRequest active again. CacheRequests can be pushed multiple times,
/// and on multiple threads; but for each thread, must be popped off in the
/// same order as they were pushed.
///
/// A CacheRequest cannot be modified while it is pushed on any thread; attempting
/// to modify it will generate an InvalidOperationException.
///
public void Push()
{
// pushing multiple times is legal,
// and pushing on different threads is also legal,
// so no preconditions to check for here.
AutomationProperty[] propertyArray = (AutomationProperty[])_properties.ToArray(typeof(AutomationProperty));
AutomationPattern[] patternArray = (AutomationPattern[])_patterns.ToArray(typeof(AutomationPattern));
// _threadStack is thread local storage (TLS) based, so can be
// accessed outside of the lock.
if (_threadStack == null)
{
_threadStack = new Stack();
}
_threadStack.Push(this);
lock (_instanceLock)
{
_refCount++;
// Generate a new UiaCacheRequest
if (_uiaCacheRequest == null)
{
_uiaCacheRequest = new UiaCoreApi.UiaCacheRequest(_viewCondition, _scope, propertyArray, patternArray, _automationElementMode);
}
}
}
///
/// Pop this CacheRequest from the current thread's stack of CacheRequests,
/// restoring the previously active CacheRequest.
///
///
/// Only the currently active CacheRequest can be popped, attempting to pop
/// a CacheRequest which is not the current one will result in an InvalidOperation
/// Exception.
///
/// The CacheRequest stack initially contains a default CacheRequest, which
/// cannot be popped off the stack.
///
public void Pop()
{
// ensure that this is top of stack
// (no lock needed here, since this is per-thread state)
if (_threadStack == null || _threadStack.Count == 0 || _threadStack.Peek() != this)
{
throw new InvalidOperationException(SR.Get(SRID.CacheReqestCanOnlyPopTop));
}
_threadStack.Pop();
lock (_instanceLock)
{
_refCount--;
}
}
///
/// Make this the currenly active CacheRequest.
///
///
/// Returns an IDisposable which should be disposed
/// when finished using this CacheRequest to deactivate it.
/// This method is designed for use within a 'using' clause.
///
public IDisposable Activate()
{
Push();
return new CacheRequestActivation(this);
}
///
/// Clone this CacheRequest
///
///
/// The returned CacheRequest contains the same request information, but is not
/// pushed on the state of any thread.
///
public CacheRequest Clone()
{
// New copy contains only temp state, not any locking state (_refCount)
return new CacheRequest(_viewCondition, _scope, (ArrayList)_properties.Clone(), (ArrayList)_patterns.Clone(), _automationElementMode, _uiaCacheRequest);
}
///
/// Add an AutomationProperty to this CacheRequest
///
/// The identifier of the property to add to this CacheRequest
public void Add(AutomationProperty property)
{
Misc.ValidateArgumentNonNull(property, "property");
lock (_instanceLock)
{
CheckAccess();
if (!_properties.Contains(property))
{
_properties.Add(property);
Invalidate();
}
}
}
///
/// Add an AutomationPattern to this CacheRequest
///
/// The identifier of the pattern to add to this CacheRequest
public void Add(AutomationPattern pattern)
{
Misc.ValidateArgumentNonNull(pattern, "pattern");
lock (_instanceLock)
{
CheckAccess();
if (!_patterns.Contains(pattern))
{
_patterns.Add(pattern);
Invalidate();
}
}
}
#endregion Public Methods
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
#region Public Properties
///
/// Indicate which nodes should be pre-fetched
///
///
/// At least one or more of of TreeScope.Element, TreeScope.Children or
/// TreeScope.Descendants must be specified.
///
/// TreeScope.Parent and TreeScope.Ancestors are not supported.
///
public TreeScope TreeScope
{
get
{
return _scope;
}
set
{
if (value == 0)
{
throw new ArgumentException(SR.Get(SRID.TreeScopeNeedAtLeastOne));
}
if ((value & ~(TreeScope.Element | TreeScope.Children | TreeScope.Descendants)) != 0)
{
throw new ArgumentException(SR.Get(SRID.TreeScopeElementChildrenDescendantsOnly));
}
lock (_instanceLock)
{
CheckAccess();
if (_scope != value)
{
_scope = value;
Invalidate();
}
}
}
}
///
/// Indicates the view to use when prefetching relative nodes
///
/// Defaults to Automation.ControlViewCondition
public Condition TreeFilter
{
get
{
return _viewCondition;
}
set
{
Misc.ValidateArgumentNonNull(value, "TreeFilter");
lock (_instanceLock)
{
CheckAccess();
if (_viewCondition != value)
{
_viewCondition = value;
Invalidate();
}
}
}
}
///
/// Specifies whether returned AutomationElements should contain
/// full references to the underlying UI, or only cached information.
///
public AutomationElementMode AutomationElementMode
{
get
{
return _automationElementMode;
}
set
{
lock (_instanceLock)
{
CheckAccess();
if (_automationElementMode != value)
{
_automationElementMode = value;
Invalidate();
}
}
}
}
///
/// Return the most recent CacheRequest which has been activated
/// by teh calling thread.
///
public static CacheRequest Current
{
get
{
if ( _threadStack == null || _threadStack.Count == 0 )
return DefaultCacheRequest;
return (CacheRequest)_threadStack.Peek();
}
}
#endregion Public Properties
//-----------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
#region Internal Properties
internal static UiaCoreApi.UiaCacheRequest DefaultUiaCacheRequest
{
get
{
if(_defaultUiaCacheRequest == null)
{
_defaultUiaCacheRequest = new UiaCoreApi.UiaCacheRequest(Automation.ControlViewCondition, TreeScope.Element, new AutomationProperty[] { AutomationElement.RuntimeIdProperty }, new AutomationPattern[] { }, AutomationElementMode.Full);
}
return _defaultUiaCacheRequest;
}
}
#endregion Internal Properties
//-----------------------------------------------------
//
// Internal Methods
//
//-----------------------------------------------------
#region Internal Methods
internal UiaCoreApi.UiaCacheRequest GetUiaCacheRequest()
{
if (_uiaCacheRequest == null)
{
AutomationProperty[] propertiesArray = (AutomationProperty[])_properties.ToArray(typeof(AutomationProperty));
AutomationPattern[] patternsArray = (AutomationPattern[])_patterns.ToArray(typeof(AutomationPattern));
lock (_instanceLock)
{
_uiaCacheRequest = new UiaCoreApi.UiaCacheRequest(_viewCondition, _scope, propertiesArray, patternsArray, _automationElementMode);
}
}
return _uiaCacheRequest;
}
static internal UiaCoreApi.UiaCacheRequest CurrentUiaCacheRequest
{
get
{
// No need to lock here, since this only uses thread state,
// and the UiaCacheRequests are generated within a lock in Push.
CacheRequest current = Current;
return current._uiaCacheRequest;
}
}
#endregion Internal Methods
//-----------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
#region Private Methods
// Ensure that this CacheRequest isn't currently in use
// Must be called within a lock(_instanceLock) to ensure
// thread consistency
void CheckAccess()
{
// Make sure this isn't being used by any thread's
// CacheRequest stacks by using a refcount:
// (Also check for defaultCacheRequest explicitly, since it
// is never explicitly added to the stack)
if (_refCount != 0 || this == DefaultCacheRequest)
{
throw new InvalidOperationException(SR.Get(SRID.CacheReqestCantModifyWhileActive));
}
}
// Called when state changes - sets _uiaCacheRequest to null
// to ensure that a clean one is generated next time Push is called
void Invalidate()
{
_uiaCacheRequest = null;
}
#endregion Private Methods
//-----------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
//--- Instance state ---
// Current mutable state...
Condition _viewCondition;
TreeScope _scope;
ArrayList _properties;
ArrayList _patterns;
AutomationElementMode _automationElementMode;
// When we Push, the current state is bundled into this, which is
// immutable. This is what the underlying requesting mechanism uses
UiaCoreApi.UiaCacheRequest _uiaCacheRequest;
// Used to track whether this instance is in use - inc'd on Push,
// dec'd on Pop...
int _refCount = 0;
// Used to lock on this instance...
object _instanceLock = null;
//--- Per-Thread state ---
// The stack of CacheRequests for this thread. Note that these need to be inited
// on-demand, as static initialization does not work with [ThreadStatic] members -
// it only applies to the first thread. Treat null as being the same as a stack with
// just DefaultCacheRequest on it.
[ThreadStatic]
private static Stack _threadStack;
//--- Global/Static state ---
internal static readonly CacheRequest DefaultCacheRequest = new CacheRequest();
internal static UiaCoreApi.UiaCacheRequest _defaultUiaCacheRequest;
#endregion Private Fields
}
//------------------------------------------------------
//
// Related utility classe
//
//-----------------------------------------------------
// Helper class returned by Access() - a using() block
// will call Dispose() on this when it goes out of scope.
internal class CacheRequestActivation : IDisposable
{
internal CacheRequestActivation(CacheRequest request)
{
_request = request;
}
public void Dispose()
{
Debug.Assert( _request != null );
if( _request != null )
{
_request.Pop();
_request = null;
}
}
// No finalizer - usually Dispose is used with a finalizer,
// but in this case, IDisposable is being used to manage scoping,
// not ensure that resources are freed.
private CacheRequest _request;
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
//----------------------------------------------------------------------------
//
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//
//
// Description: Class that describes the data to be pre-fected in Automation
// element operations, and manange the current request.
//
// History:
// 02/05/2004 : BrendanM Ported to WCP
//
//---------------------------------------------------------------------------
using System;
using System.Collections;
using System.Diagnostics;
using System.Windows.Automation;
using MS.Internal.Automation;
namespace System.Windows.Automation
{
///
/// Specified type of reference to use when returning AutomationElements
///
///
/// AutomationElementMode.Full is the default, and specified that returned AutomationElements
/// contain a full reference to the underlying UI.
///
/// AutomationElementMode.None specifies taht the returned AutomationElements have no
/// reference to the underlying UI, and contain only cached information.
///
/// Certain operations on AutomationElements, such as GetCurrentProperty
/// or SetFocus require a full reference; attempting to perform these on an
/// AutomationElement that has AutomationElementMode.None will result in an
/// InvalidOperationException being thrown.
///
/// Using AutomationElementMode.None can be more efficient when only properties are needed,
/// as it avoids the overhead involved in setting up full references.
///
#if (INTERNAL_COMPILE)
internal enum AutomationElementMode
#else
public enum AutomationElementMode
#endif
{
///
/// Specifies that returned AutomationElements have no reference to the
/// underlying UI, and contain only cached information.
///
None,
///
/// Specifies that returned AutomationElements have a full reference to the
/// underlying UI.
///
Full
}
// Implementation notes:
//
// CacheRequest is the user-facing class that is used to build up
// cache requests, using Add and the other properties. When activated,
// the data is gathered into a UiaCacheRequest instance, which is
// immutable - these are what the rest of UIA uses internally.
//
// The default cache request - which appears to be always at the bottom
// of the stack and which cannot be moved - is not actually part of the
// stack. Instead, current returns it whever the stack is empty.
///
/// Class used to specify the properties and patterns that should be
/// prefetched by UIAutomation when returning AutomationElements.
///
#if (INTERNAL_COMPILE)
internal sealed class CacheRequest
#else
public sealed class CacheRequest
#endif
{
//-----------------------------------------------------
//
// Constructors
//
//-----------------------------------------------------
#region Constructors
///
/// Create a new CacheRequest with default values.
///
///
/// A Thread's current CacheRequest determins which properties,
/// patterns and relative elements - if any - are pre-fetched by
/// AutomationElement.
///
/// A default cache request works on the Control view of the tree,
/// and does not prefetch any properties or patterns.
///
/// Use .Push or .Activate to make the CacheRequest the current active
/// CacheRequest for the current thread.
///
public CacheRequest()
{
_instanceLock = new object();
_viewCondition = Automation.ControlViewCondition;
_scope = TreeScope.Element;
_properties = new ArrayList();
_patterns = new ArrayList();
_automationElementMode = AutomationElementMode.Full;
// We always want RuntimeID to be available...
_properties.Add(AutomationElement.RuntimeIdProperty);
_uiaCacheRequest = DefaultUiaCacheRequest;
}
// Private ctor used by Clone()
private CacheRequest( Condition viewCondition,
TreeScope scope,
ArrayList properties,
ArrayList patterns,
AutomationElementMode automationElementMode,
UiaCoreApi.UiaCacheRequest uiaCacheRequest)
{
_instanceLock = new object();
_viewCondition = viewCondition;
_scope = scope;
_properties = properties;
_patterns = patterns;
_automationElementMode = automationElementMode;
_uiaCacheRequest = uiaCacheRequest;
}
#endregion Constructors
//------------------------------------------------------
//
// Public Methods
//
//-----------------------------------------------------
#region Public Methods
///
/// Push this CacheRequest onto this thread's stack of CacheRequests,
/// making it the current CacheRequest for this thread.
///
///
/// Use Pop to remove this CacheRequest from the stack, making the previously
/// active CacheRequest active again. CacheRequests can be pushed multiple times,
/// and on multiple threads; but for each thread, must be popped off in the
/// same order as they were pushed.
///
/// A CacheRequest cannot be modified while it is pushed on any thread; attempting
/// to modify it will generate an InvalidOperationException.
///
public void Push()
{
// pushing multiple times is legal,
// and pushing on different threads is also legal,
// so no preconditions to check for here.
AutomationProperty[] propertyArray = (AutomationProperty[])_properties.ToArray(typeof(AutomationProperty));
AutomationPattern[] patternArray = (AutomationPattern[])_patterns.ToArray(typeof(AutomationPattern));
// _threadStack is thread local storage (TLS) based, so can be
// accessed outside of the lock.
if (_threadStack == null)
{
_threadStack = new Stack();
}
_threadStack.Push(this);
lock (_instanceLock)
{
_refCount++;
// Generate a new UiaCacheRequest
if (_uiaCacheRequest == null)
{
_uiaCacheRequest = new UiaCoreApi.UiaCacheRequest(_viewCondition, _scope, propertyArray, patternArray, _automationElementMode);
}
}
}
///
/// Pop this CacheRequest from the current thread's stack of CacheRequests,
/// restoring the previously active CacheRequest.
///
///
/// Only the currently active CacheRequest can be popped, attempting to pop
/// a CacheRequest which is not the current one will result in an InvalidOperation
/// Exception.
///
/// The CacheRequest stack initially contains a default CacheRequest, which
/// cannot be popped off the stack.
///
public void Pop()
{
// ensure that this is top of stack
// (no lock needed here, since this is per-thread state)
if (_threadStack == null || _threadStack.Count == 0 || _threadStack.Peek() != this)
{
throw new InvalidOperationException(SR.Get(SRID.CacheReqestCanOnlyPopTop));
}
_threadStack.Pop();
lock (_instanceLock)
{
_refCount--;
}
}
///
/// Make this the currenly active CacheRequest.
///
///
/// Returns an IDisposable which should be disposed
/// when finished using this CacheRequest to deactivate it.
/// This method is designed for use within a 'using' clause.
///
public IDisposable Activate()
{
Push();
return new CacheRequestActivation(this);
}
///
/// Clone this CacheRequest
///
///
/// The returned CacheRequest contains the same request information, but is not
/// pushed on the state of any thread.
///
public CacheRequest Clone()
{
// New copy contains only temp state, not any locking state (_refCount)
return new CacheRequest(_viewCondition, _scope, (ArrayList)_properties.Clone(), (ArrayList)_patterns.Clone(), _automationElementMode, _uiaCacheRequest);
}
///
/// Add an AutomationProperty to this CacheRequest
///
/// The identifier of the property to add to this CacheRequest
public void Add(AutomationProperty property)
{
Misc.ValidateArgumentNonNull(property, "property");
lock (_instanceLock)
{
CheckAccess();
if (!_properties.Contains(property))
{
_properties.Add(property);
Invalidate();
}
}
}
///
/// Add an AutomationPattern to this CacheRequest
///
/// The identifier of the pattern to add to this CacheRequest
public void Add(AutomationPattern pattern)
{
Misc.ValidateArgumentNonNull(pattern, "pattern");
lock (_instanceLock)
{
CheckAccess();
if (!_patterns.Contains(pattern))
{
_patterns.Add(pattern);
Invalidate();
}
}
}
#endregion Public Methods
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
#region Public Properties
///
/// Indicate which nodes should be pre-fetched
///
///
/// At least one or more of of TreeScope.Element, TreeScope.Children or
/// TreeScope.Descendants must be specified.
///
/// TreeScope.Parent and TreeScope.Ancestors are not supported.
///
public TreeScope TreeScope
{
get
{
return _scope;
}
set
{
if (value == 0)
{
throw new ArgumentException(SR.Get(SRID.TreeScopeNeedAtLeastOne));
}
if ((value & ~(TreeScope.Element | TreeScope.Children | TreeScope.Descendants)) != 0)
{
throw new ArgumentException(SR.Get(SRID.TreeScopeElementChildrenDescendantsOnly));
}
lock (_instanceLock)
{
CheckAccess();
if (_scope != value)
{
_scope = value;
Invalidate();
}
}
}
}
///
/// Indicates the view to use when prefetching relative nodes
///
/// Defaults to Automation.ControlViewCondition
public Condition TreeFilter
{
get
{
return _viewCondition;
}
set
{
Misc.ValidateArgumentNonNull(value, "TreeFilter");
lock (_instanceLock)
{
CheckAccess();
if (_viewCondition != value)
{
_viewCondition = value;
Invalidate();
}
}
}
}
///
/// Specifies whether returned AutomationElements should contain
/// full references to the underlying UI, or only cached information.
///
public AutomationElementMode AutomationElementMode
{
get
{
return _automationElementMode;
}
set
{
lock (_instanceLock)
{
CheckAccess();
if (_automationElementMode != value)
{
_automationElementMode = value;
Invalidate();
}
}
}
}
///
/// Return the most recent CacheRequest which has been activated
/// by teh calling thread.
///
public static CacheRequest Current
{
get
{
if ( _threadStack == null || _threadStack.Count == 0 )
return DefaultCacheRequest;
return (CacheRequest)_threadStack.Peek();
}
}
#endregion Public Properties
//-----------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
#region Internal Properties
internal static UiaCoreApi.UiaCacheRequest DefaultUiaCacheRequest
{
get
{
if(_defaultUiaCacheRequest == null)
{
_defaultUiaCacheRequest = new UiaCoreApi.UiaCacheRequest(Automation.ControlViewCondition, TreeScope.Element, new AutomationProperty[] { AutomationElement.RuntimeIdProperty }, new AutomationPattern[] { }, AutomationElementMode.Full);
}
return _defaultUiaCacheRequest;
}
}
#endregion Internal Properties
//-----------------------------------------------------
//
// Internal Methods
//
//-----------------------------------------------------
#region Internal Methods
internal UiaCoreApi.UiaCacheRequest GetUiaCacheRequest()
{
if (_uiaCacheRequest == null)
{
AutomationProperty[] propertiesArray = (AutomationProperty[])_properties.ToArray(typeof(AutomationProperty));
AutomationPattern[] patternsArray = (AutomationPattern[])_patterns.ToArray(typeof(AutomationPattern));
lock (_instanceLock)
{
_uiaCacheRequest = new UiaCoreApi.UiaCacheRequest(_viewCondition, _scope, propertiesArray, patternsArray, _automationElementMode);
}
}
return _uiaCacheRequest;
}
static internal UiaCoreApi.UiaCacheRequest CurrentUiaCacheRequest
{
get
{
// No need to lock here, since this only uses thread state,
// and the UiaCacheRequests are generated within a lock in Push.
CacheRequest current = Current;
return current._uiaCacheRequest;
}
}
#endregion Internal Methods
//-----------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
#region Private Methods
// Ensure that this CacheRequest isn't currently in use
// Must be called within a lock(_instanceLock) to ensure
// thread consistency
void CheckAccess()
{
// Make sure this isn't being used by any thread's
// CacheRequest stacks by using a refcount:
// (Also check for defaultCacheRequest explicitly, since it
// is never explicitly added to the stack)
if (_refCount != 0 || this == DefaultCacheRequest)
{
throw new InvalidOperationException(SR.Get(SRID.CacheReqestCantModifyWhileActive));
}
}
// Called when state changes - sets _uiaCacheRequest to null
// to ensure that a clean one is generated next time Push is called
void Invalidate()
{
_uiaCacheRequest = null;
}
#endregion Private Methods
//-----------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
//--- Instance state ---
// Current mutable state...
Condition _viewCondition;
TreeScope _scope;
ArrayList _properties;
ArrayList _patterns;
AutomationElementMode _automationElementMode;
// When we Push, the current state is bundled into this, which is
// immutable. This is what the underlying requesting mechanism uses
UiaCoreApi.UiaCacheRequest _uiaCacheRequest;
// Used to track whether this instance is in use - inc'd on Push,
// dec'd on Pop...
int _refCount = 0;
// Used to lock on this instance...
object _instanceLock = null;
//--- Per-Thread state ---
// The stack of CacheRequests for this thread. Note that these need to be inited
// on-demand, as static initialization does not work with [ThreadStatic] members -
// it only applies to the first thread. Treat null as being the same as a stack with
// just DefaultCacheRequest on it.
[ThreadStatic]
private static Stack _threadStack;
//--- Global/Static state ---
internal static readonly CacheRequest DefaultCacheRequest = new CacheRequest();
internal static UiaCoreApi.UiaCacheRequest _defaultUiaCacheRequest;
#endregion Private Fields
}
//------------------------------------------------------
//
// Related utility classe
//
//-----------------------------------------------------
// Helper class returned by Access() - a using() block
// will call Dispose() on this when it goes out of scope.
internal class CacheRequestActivation : IDisposable
{
internal CacheRequestActivation(CacheRequest request)
{
_request = request;
}
public void Dispose()
{
Debug.Assert( _request != null );
if( _request != null )
{
_request.Pop();
_request = null;
}
}
// No finalizer - usually Dispose is used with a finalizer,
// but in this case, IDisposable is being used to manage scoping,
// not ensure that resources are freed.
private CacheRequest _request;
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
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- XmlDataSource.cs
- VisualBasicSettingsConverter.cs
- Timer.cs
- PartitionedStream.cs
- ConvertEvent.cs
- PaintValueEventArgs.cs
- ResXResourceWriter.cs
- XXXOnTypeBuilderInstantiation.cs
- TimeSpanConverter.cs
- oledbmetadatacolumnnames.cs
- UrlUtility.cs
- FrameSecurityDescriptor.cs
- StyleBamlTreeBuilder.cs
- AppDomain.cs
- InfoCardSchemas.cs
- TransformPattern.cs
- DataGridClipboardHelper.cs
- RootProfilePropertySettingsCollection.cs
- DefaultEvaluationContext.cs
- ListViewPagedDataSource.cs
- XPathMessageFilterElementCollection.cs
- X509CertificateCollection.cs
- RemoteWebConfigurationHostStream.cs
- ValidationErrorCollection.cs
- SplitterCancelEvent.cs
- RuleRefElement.cs
- DataContractSerializerServiceBehavior.cs
- DiscoveryServiceExtension.cs
- Opcode.cs
- CodeDOMUtility.cs
- SimpleLine.cs
- OutputCacheSection.cs
- TemplateBuilder.cs
- XmlSchemas.cs
- FormsAuthenticationEventArgs.cs
- TemplatedAdorner.cs
- CompiledXpathExpr.cs
- ByteAnimation.cs
- XmlDictionaryReaderQuotasElement.cs
- DataGridViewTopRowAccessibleObject.cs
- EmptyEnumerator.cs
- TextPointer.cs
- TextView.cs
- Function.cs
- ParameterModifier.cs
- WebPartPersonalization.cs
- DiscoveryVersion.cs
- TemplateAction.cs
- SqlDataSourceQueryEditor.cs
- ObjectDataSourceSelectingEventArgs.cs
- EntitySet.cs
- WebPartDisplayMode.cs
- EntitySetBase.cs
- RsaSecurityTokenAuthenticator.cs
- SecUtil.cs
- TransactionFormatter.cs
- Schema.cs
- ComponentDesigner.cs
- EventDescriptorCollection.cs
- XpsResource.cs
- Floater.cs
- HintTextMaxWidthConverter.cs
- JsonObjectDataContract.cs
- ServiceDiscoveryBehavior.cs
- QuaternionAnimationBase.cs
- TextSelectionProcessor.cs
- ForceCopyBuildProvider.cs
- PropertyItemInternal.cs
- Latin1Encoding.cs
- ClientRoleProvider.cs
- SystemKeyConverter.cs
- RepeatBehavior.cs
- LingerOption.cs
- OrderByLifter.cs
- Serializer.cs
- DependencyPropertyKind.cs
- XmlMapping.cs
- DataControlCommands.cs
- TextTreeTextNode.cs
- FontStretch.cs
- DesignDataSource.cs
- InternalBufferManager.cs
- SettingsPropertyCollection.cs
- MultipartContentParser.cs
- ClientData.cs
- SourceFileBuildProvider.cs
- ForceCopyBuildProvider.cs
- X509Utils.cs
- CommandEventArgs.cs
- DBSqlParserColumnCollection.cs
- TableAutomationPeer.cs
- DataSvcMapFileSerializer.cs
- QueryOperationResponseOfT.cs
- CompilerState.cs
- CodeSnippetTypeMember.cs
- SymmetricCryptoHandle.cs
- TextEditorLists.cs
- DispatcherHooks.cs