std::filesystem::path::root_name

 

C++

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功能特性测试宏(C++20)

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符号索引

外部库

 

文件系统库

类
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
函数
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
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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

 

std::filesystem::path

成员类型
成员常量
path::native_formatpath::generic_formatpath::auto_format
成员函数
path::path path::~path path::operator= path::assign path::appendpath::operator/= path::concatpath::operator+= path::clear path::make_preferred path::remove_filename path::replace_filename path::replace_extension    path::swap path::compare path::beginpath::end	path::c_strpath::nativepath::operator string_type path::stringpath::u8stringpath::u16stringpath::u32stringpath::wstring path::generic_stringpath::generic_u8stringpath::generic_u16stringpath::generic_u32stringpath::generic_wstring path::lexically_normalpath::lexically_relativepath::lexically_proximate
路径分解
path::root_name path::root_directory path::root_path path::relative_path path::parent_path path::filename path::stem path::extension path::empty	path::has_root_pathpath::has_root_namepath::has_root_directorypath::has_relative_pathpath::has_parent_pathpath::has_filenamepath::has_stempath::has_extension path::is_absolutepath::is_relative
非成员函数
operator==operator!=operator<operator<=operator>operator>=operator<=> (C++20 前)(C++20 前)(C++20 前)(C++20 前)(C++20 前)(C++20)	operator/ operator<<operator>> swap(std::filesystem::path) hash_value u8path
辅助类
hash<std::filesystem::path>	formatter<std::filesystem::path> (C++26)

 

path root_name()const;		(C++17 起)

返回通用格式路径的根名。若路径（以通用格式）不包含根名，则返回 path()。

参数

（无）

返回值

路径的根名。

异常

可能会抛出由实现定义的异常。

示例

运行此代码

#include <filesystem>#include <iostream>namespace fs = std::filesystem;   int main(){std::cout<<"当前根名为: "<< fs::current_path().root_name()<<'\n';}

可能的输出：

当前根名为: "C:"

参阅

root_directory	若存在则返回路径的根目录 (公开成员函数)
root_path	若存在则返回路径的根路径 (公开成员函数)