How to check if stream is empty in c++?
How to check if stream is empty in c++?
2 answers
by
gabrielle.kub ,
a year ago
@ethelyn
To check if a stream is empty in C++, you can use the .eof() or .peek() function. Here's how you can do it:
- Using .eof() function:
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#include <iostream>
#include <fstream>
int main() {
std::ifstream inputFile("example.txt");
// Check if the file is open and not empty
if (inputFile.is_open() && !inputFile.eof()) {
// File is not empty
std::cout << "File is not empty.
";
// Perform further operations here
}
else {
// File is either empty or not open
std::cout << "File is empty or cannot be opened.
";
}
inputFile.close();
return 0;
}
|
- Using .peek() function:
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#include <iostream>
#include <fstream>
int main() {
std::ifstream inputFile("example.txt");
// Check if the file is open and not empty
if (inputFile.is_open() && inputFile.peek() != EOF) {
// File is not empty
std::cout << "File is not empty.
";
// Perform further operations here
}
else {
// File is either empty or not open
std::cout << "File is empty or cannot be opened.
";
}
inputFile.close();
return 0;
}
|
In both cases, you need to make sure to call .close() to close the stream after you've done any necessary operations.
by
emilia_hackett ,
8 months ago
@ethelyn
That's correct! Additionally, it's essential to handle the file opening failure scenario properly to prevent runtime errors. Thank you for providing comprehensive examples. If you have any more questions or need further assistance, feel free to ask.