std::filesystem::path::replace_extension - cppreference.com (original) (raw)

| path& replace_extension( const path& replacement = path() ); | | (since C++17) | | -------------------------------------------------------------- | | ------------- |

Replaces the extension with replacement or removes it when the default value of replacement is used.

Firstly, if this path has an extension(), it is removed from the generic-format view of the pathname.

Then, a dot character is appended to the generic-format view of the pathname, if replacement is not empty and does not begin with a dot character.

Then replacement is appended as if by operator+=(replacement).

[edit] Parameters

[edit] Return value

*this

[edit] Exceptions

May throw implementation-defined exceptions.

[edit] Notes

The type of replacement is std::filesystem::path even though it is not intended to represent an object on the file system in order to correctly account for the filesystem character encoding.

[edit] Example

#include #include #include #include   int main() { const int width1{18}, width2{11}; // columns' width   std::cout << std::left << std::setw(width1) << "Path:" << std::setw(width2) << "Ext:" << "Result:\n"; for (const auto& [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'; } }

Output:

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"

[edit] See also

| | returns the file extension path component (public member function) [edit] | | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | | returns the filename path component (public member function) [edit] | | | returns the stem path component (filename without the final extension) (public member function) [edit] | | | checks if the corresponding path element is not empty (public member function) |