std::filesystem::file_time_type

 

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filesystem::path filesystem::filesystem_error filesystem::directory_entry filesystem::directory_iterator filesystem::recursive_directory_iterator    filesystem::file_status filesystem::space_info	filesystem::file_type filesystem::file_time_type filesystem::perms filesystem::perm_options filesystem::copy_options filesystem::directory_options
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filesystem::absolute filesystem::canonicalfilesystem::weakly_canonical filesystem::relativefilesystem::proximate filesystem::copy filesystem::copy_file filesystem::copy_symlink filesystem::create_directory filesystem::create_directories filesystem::create_hard_link filesystem::create_symlink filesystem::create_directory_symlink filesystem::current_path filesystem::temp_directory_path	filesystem::exists filesystem::equivalent filesystem::file_size filesystem::hard_link_count filesystem::last_write_time filesystem::permissions filesystem::read_symlink filesystem::remove filesystem::remove_all filesystem::rename filesystem::resize_file filesystem::space filesystem::status filesystem::symlink_status
檔案型別
filesystem::is_block_file filesystem::is_character_file filesystem::is_directory filesystem::is_empty filesystem::status_known	filesystem::is_fifo filesystem::is_other filesystem::is_regular_file filesystem::is_socket filesystem::is_symlink

 

定義於標頭檔案 <filesystem>
using file_time_type = std::chrono::time_point</*trivial-clock*/>;		(C++17 起) (C++20 前)
using file_time_type = std::chrono::time_point<std::chrono::file_clock>;		(C++20 起)

表示檔案時間。

/*trivial-clock*/ 是一個實現定義的型別，滿足 TrivialClock 且足以表示檔案系統所提供檔案時間值的精度和範圍。

(C++20 前)

示例

執行此程式碼

#include <chrono>
#include <filesystem>
#include <format>
#include <fstream>
#include <iostream>
 
using namespace std::chrono_literals;
 
int main()
{
    auto p = std::filesystem::temp_directory_path() / "example.bin";
    std::ofstream{p.c_str()}.put('a'); // create file
 
    std::filesystem::file_time_type ftime = std::filesystem::last_write_time(p);
    std::cout << std::format("File write time is {}\n", ftime);
 
    // move file write time 1 hour to the future
    std::filesystem::last_write_time(p, ftime + 1h);
 
    // read back from the filesystem
    ftime = std::filesystem::last_write_time(p);
    std::cout << std::format("File write time is {}\n", ftime);
 
    std::filesystem::remove(p);
}

可能的輸出

File write time is 2023-09-04 19:33:24.702639224
File write time is 2023-09-04 20:33:24.702639224

參閱

last_write_time (C++17)

獲取或設定最後資料修改時間 (函式)