handlet-class.md

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Learn more about: HandleT Class	HandleT Class	10/03/2018	reference	corewrappers/Microsoft::WRL::Wrappers::HandleT corewrappers/Microsoft::WRL::Wrappers::HandleT::Attach corewrappers/Microsoft::WRL::Wrappers::HandleT::Close corewrappers/Microsoft::WRL::Wrappers::HandleT::Detach corewrappers/Microsoft::WRL::Wrappers::HandleT::Get corewrappers/Microsoft::WRL::Wrappers::HandleT::handle_ corewrappers/Microsoft::WRL::Wrappers::HandleT::HandleT corewrappers/Microsoft::WRL::Wrappers::HandleT::InternalClose corewrappers/Microsoft::WRL::Wrappers::HandleT::IsValid corewrappers/Microsoft::WRL::Wrappers::HandleT::operator= corewrappers/Microsoft::WRL::Wrappers::HandleT::~HandleT	Microsoft::WRL::Wrappers::HandleT class Microsoft::WRL::Wrappers::HandleT::Attach method Microsoft::WRL::Wrappers::HandleT::Close method Microsoft::WRL::Wrappers::HandleT::Detach method Microsoft::WRL::Wrappers::HandleT::Get method Microsoft::WRL::Wrappers::HandleT::handle_ data member Microsoft::WRL::Wrappers::HandleT::HandleT, constructor Microsoft::WRL::Wrappers::HandleT::InternalClose method Microsoft::WRL::Wrappers::HandleT::IsValid method Microsoft::WRL::Wrappers::HandleT::operator= operator Microsoft::WRL::Wrappers::HandleT::~HandleT, destructor	3822b32a-a426-4d94-a54d-919d4df60ee2

HandleT Class

Represents a handle to an object.

Syntax

template <typename HandleTraits>
class HandleT;

Parameters

HandleTraits
An instance of the HandleTraits structure that defines common characteristics of a handle.

Members

Public Typedefs

Name	Description
Traits	A synonym for HandleTraits.

Public Constructors

Name	Description
HandleT::HandleT	Initializes a new instance of the HandleT class.
HandleT::~HandleT	Deinitializes an instance of the HandleT class.

Public Methods

Name	Description
HandleT::Attach	Associates the specified handle with the current HandleT object.
HandleT::Close	Closes the current HandleT object.
HandleT::Detach	Disassociates the current HandleT object from its underlying handle.
HandleT::Get	Gets the value of the underlying handle.
HandleT::IsValid	Indicates whether the current HandleT object represents a handle.

Protected Methods

Name	Description
HandleT::InternalClose	Closes the current HandleT object.

Public Operators

Name	Description
HandleT::operator=	Moves the value of the specified HandleT object to the current HandleT object.

Protected Data Members

Name	Description
HandleT::handle_	Contains the handle that is represented by the HandleT object.

Inheritance Hierarchy

HandleT

Requirements

Header: corewrappers.h

Namespace: Microsoft::WRL::Wrappers

HandleT::~HandleT

Deinitializes an instance of the HandleT class.

~HandleT();

HandleT::Attach

Associates the specified handle with the current HandleT object.

void Attach(
   typename HandleTraits::Type h
);

Parameters

h
A handle.

HandleT::Close

Closes the current HandleT object.

void Close();

Remarks

The handle that underlies the current HandleT is closed, and the HandleT is set to the invalid state.

If the handle doesn't close properly, an exception is raised in the calling thread.

HandleT::Detach

Disassociates the current HandleT object from its underlying handle.

typename HandleTraits::Type Detach();

Return Value

The underlying handle.

Remarks

When this operation completes, the current HandleT is set to the invalid state.

HandleT::Get

Gets the value of the underlying handle.

typename HandleTraits::Type Get() const;

Return Value

A handle.

HandleT::handle_

Contains the handle that is represented by the HandleT object.

typename HandleTraits::Type handle_;

HandleT::HandleT

Initializes a new instance of the HandleT class.

explicit HandleT(
   typename HandleTraits::Type h =
      HandleTraits::GetInvalidValue()
);

HandleT(
   _Inout_ HandleT&& h
);

Parameters

h
A handle.

Remarks

The first constructor initializes a HandleT object that is not a valid handle to an object. The second constructor creates a new HandleT object from parameter h.

HandleT::InternalClose

Closes the current HandleT object.

virtual bool InternalClose();

Return Value

true if the current HandleT closed successfully; otherwise, false.

Remarks

InternalClose() is protected.

HandleT::IsValid

Indicates whether the current HandleT object represents a handle.

bool IsValid() const;

Return Value

true if the HandleT represents a handle; otherwise, false.

HandleT::operator=

Moves the value of the specified HandleT object to the current HandleT object.

HandleT& operator=(
   _Inout_ HandleT&& h
);

Parameters

h
An rvalue-reference to a handle.

Return Value

A reference to the current HandleT object.

Remarks

This operation invalidates the HandleT object specified by parameter h.