std::filesystem::path::replace_extension

 

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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
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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
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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& replace_extension(const path& replacement = path());		(C++17 起)

以 replacement 替换扩展名，或在使用 replacement 的默认值时移除它。

首先，若此路径拥有 extension()，则首先从路径名的通用格式视角移除它。

然后若 replacement 非空且不以句点字符开始，则添加句点字符到路径名的通用格式视图。

然后如同用 operator+=(replacement) 后附 replacement。

参数

replacement

-

要替换的扩展名

返回值

*this

异常

可能会抛出由实现定义的异常。

注解

replacement 的类型是 std::filesystem::path，即使并非有意用它表示文件系统上的对象，这是为了正确认定文件系统字符编码。

示例

运行此代码

#include <filesystem>#include <iomanip>#include <iostream>#include <utility>   int main(){constint width1{18}, width2{11};// columns' width   std::cout<<std::left<<std::setw(width1)<<"Path:"<<std::setw(width2)<<"Ext:"<<"Result:\n";for(constauto&[p, e]:{std::make_pair("/foo/bar.jpg", ".png"), {"/foo/bar.jpg", "png"}, {"/foo/bar.jpg", "."}, {"/foo/bar.jpg", ""}, {"/foo/bar.", "png"}, {"/foo/bar", ".png"}, {"/foo/bar", "png"}, {"/foo/bar", "."}, {"/foo/bar", ""}, {"/foo/.", ".png"}, {"/foo/.", "png"}, {"/foo/.", "."}, {"/foo/.", ""}, {"/foo/", ".png"}, {"/foo/", "png"}}){std::filesystem::path path{p}, ext{e};std::cout<<std::setw(width1)<< path <<std::setw(width2)<< ext; path.replace_extension(ext);std::cout<< path <<'\n';}}

输出：

Path: Ext: Result: "/foo/bar.jpg" ".png" "/foo/bar.png" "/foo/bar.jpg" "png" "/foo/bar.png" "/foo/bar.jpg" "." "/foo/bar." "/foo/bar.jpg" "" "/foo/bar" "/foo/bar." "png" "/foo/bar.png" "/foo/bar" ".png" "/foo/bar.png" "/foo/bar" "png" "/foo/bar.png" "/foo/bar" "." "/foo/bar." "/foo/bar" "" "/foo/bar" "/foo/." ".png" "/foo/..png" "/foo/." "png" "/foo/..png" "/foo/." "." "/foo/.." "/foo/." "" "/foo/." "/foo/" ".png" "/foo/.png" "/foo/" "png" "/foo/.png"

参阅

extension	返回文件扩展名路径组分 (公开成员函数)
filename	返回文件名路径组分 (公开成员函数)
stem	返回主干路径组分（不带扩展名的文件名） (公开成员函数)
has_extension	检查对应路径元素是否非空 (公开成员函数)