winrt::clock struct (C++/WinRT)

A type containing static helper functions for converting a Windows::Foundation::DateTime (that is, a std::chrono::time_point) to and from winrt::file_time, and to and from time_t.

winrt::clock is defined as using the same units as Windows::Foundation::DateTime (a signed 64-bit integer of 100-nanosecond intervals since Jan 1 1601). Other C++ standard clocks don't typically define their resolution, and don't use the epoch Jan 1 1601, which is a Windows Runtime/FILETIME epoch.

Syntax

struct clock

Requirements

Minimum supported SDK: Windows SDK version 10.0.17134.0 (Windows 10, version 1803)

Namespace: winrt

Header: %WindowsSdkDir%Include<WindowsTargetPlatformVersion>\cppwinrt\winrt\base.h (included by default)

Member type aliases

Alias name	Type
clock::rep	A synonym for int64_t.
clock::period	A synonym for Windows::Foundation::TimeSpan::period.
clock::duration	A synonym for Windows::Foundation::TimeSpan.
clock::time_point	A synonym for Windows::Foundation::DateTime.

Member functions

Function	Description
clock::now function	Retrieves the current time as a Windows::Foundation::DateTime.
clock::from_file_time function	Converts a winrt::file_time value to a Windows::Foundation::DateTime.
clock::from_time_t function	Converts a time_t value to a Windows::Foundation::DateTime.
clock::to_file_time function	Converts a Windows::Foundation::DateTime value to a winrt::file_time.
clock::to_time_t function	Converts a Windows::Foundation::DateTime value to a time_t.

clock::now function

Retrieves the current time as a Windows::Foundation::DateTime.

Syntax

static Windows::Foundation::DateTime now() noexcept;

Return value

The current time as a Windows::Foundation::DateTime.

clock::from_file_time function

Converts a winrt::file_time value to a Windows::Foundation::DateTime.

Syntax

static Windows::Foundation::DateTime from_file_time(winrt::file_time const& time) noexcept;

Parameters

time A winrt::file_time value to convert to a Windows::Foundation::DateTime.

Return value

The winrt::file_time value converted into a Windows::Foundation::DateTime.

clock::from_time_t function

Converts a time_t value to a Windows::Foundation::DateTime.

Syntax

static Windows::Foundation::DateTime from_time_t(time_t time) noexcept;

Parameters

time A time_t value to convert to a Windows::Foundation::DateTime.

Return value

The time_t value converted into a Windows::Foundation::DateTime.

clock::to_file_time function

Converts a Windows::Foundation::DateTime value to a winrt::file_time.

Syntax

static file_time to_file_time(Windows::Foundation::DateTime const& time) noexcept;

Parameters

time A Windows::Foundation::DateTime value to convert to a winrt::file_time.

Return value

The Windows::Foundation::DateTime value converted into a winrt::file_time.

clock::to_time_t function

Converts a Windows::Foundation::DateTime value to a time_t.

Syntax

static time_t to_time_t(Windows::Foundation::DateTime const& time) noexcept;

Parameters

time A Windows::Foundation::DateTime value to convert to a time_t*.

Return value

The Windows::Foundation::DateTime value converted into a time_t.

See also

• winrt namespace
• FILETIME
• std::chrono::time_point
• time_t
• Windows::Foundation::DateTime