File open and close operations in C++ - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to open a file named "data.txt" for reading.

C++

#include <fstream>

int main() {
    std::ifstream file;
    file.[1]("data.txt");
    return 0;
}

Drag options to blanks, or click blank then click option'

Aclose

Bopen

Cread

Dwrite

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'close' instead of 'open' to start file access.

Trying to use 'read' or 'write' directly without opening the file.

The open function is used to open a file stream in C++.

2fill in blank

medium

Complete the code to check if the file was successfully opened.

C++

#include <fstream>
#include <iostream>

int main() {
    std::ifstream file("data.txt");
    if (!file.[1]()) {
        std::cout << "Failed to open file." << std::endl;
    }
    return 0;
}

Drag options to blanks, or click blank then click option'

Aclose

Bopen

Cis_open

Dfail

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'open()' instead of 'is_open()' to check file status.

Using 'fail()' which checks for failure but not specifically if open.

The is_open() function returns true if the file is open.

3fill in blank

hard

Fix the error in closing the file stream.

C++

#include <fstream>

int main() {
    std::ofstream file("output.txt");
    // Write something to file
    file << "Hello!";
    file.[1]();
    return 0;
}

Drag options to blanks, or click blank then click option'

Awrite

Bflush

Copen

Dclose

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'open()' to close the file.

Using 'flush()' which only clears buffers but does not close.

The close() function properly closes the file stream.

4fill in blank

hard

Fill both blanks to open a file for writing and check if it opened successfully.

C++

#include <fstream>
#include <iostream>

int main() {
    std::ofstream file;
    file.[1]("log.txt");
    if (!file.[2]()) {
        std::cout << "Cannot open file." << std::endl;
    }
    return 0;
}

Drag options to blanks, or click blank then click option'

Aopen

Bclose

Cis_open

Dfail

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'close' instead of 'open' to open the file.

Using 'fail' instead of 'is_open' to check file status.

Use open() to open the file and is_open() to check if it opened.

5fill in blank

hard

Fill all three blanks to open a file, write "Test" to it, and then close it.

C++

#include <fstream>

int main() {
    std::ofstream file;
    file.[1]("test.txt");
    file << [2];
    file.[3]();
    return 0;
}

Drag options to blanks, or click blank then click option'

Aopen

B"Test"

Cclose

Dwrite

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to open the file before writing.

Not closing the file after writing.

Open the file with open(), write the string "Test", then close with close().