std::basic_ifstream::is_open
From cppreference.com
< cpp | io | basic ifstream
| bool is_open();
|
(until C++11) | |
| bool is_open() const;
|
(since C++11) | |
Checks if the file stream has an associated file.
Effectively calls rdbuf()->is_open().
Contents |
[edit] Parameters
(none)
[edit] Return value
true if the file stream has an associated file, false otherwise
[edit] Example
Run this code
#include <string> #include <fstream> #include <iostream> //this file is called main.cpp bool file_exists(const std::string& str) { std::ifstream fs(str); return fs.is_open(); } int main() { std::boolalpha(std::cout); std::cout << file_exists("main.cpp") << '\n' << file_exists("strange_file") << '\n'; }
Possible output:
true false
[edit] See also
| opens a file and associates it with the stream (public member function) |
|
| closes the associated file (public member function) |