Appending Data to a File

Appending data to a file allows you to add new content without erasing existing information. This is accomplished using the ios::app file mode with ofstream

Example:-

ofstream file(“log.txt”, ios::app);

file << “New log entry.\n”;

file.close();

Updating Data in a File

Updating data in a file refers to the process of modifying, replacing, or appending information within an existing file without recreating it from scratch. In C++, this typically involves reading the file contents, applying changes in memory, and writing the updated data back to the file.

Example:

fstream file(“data.txt”, ios::in | ios::out);

string line;

getline(file, line);

file.seekp(0);

file << “Updated Line”;

file.close();

File Streams as Class Members

You can declare ifstream (input file stream) or ofstream (output file stream) objects as data members of a class to encapsulate file-related operations. This approach promotes modularity by associating file-handling functionality directly with the class that needs it.

Key Advantages:

• Encapsulates file operations within a specific class, promoting better structure.
• Simplifies usage by hiding stream initialization and management inside member functions.
• Supports object-oriented principles like abstraction and reusability.

Advantages of File Handling in C++

1. Persistent Storage: Data is saved even after program ends.
2. Automated Logging: Useful for maintaining logs and records.
3. Reusable Data: Allows programs to share and reuse files.
4. Large Data Management: Handles large datasets efficiently.
5. Binary and Text Support: Flexible for different data formats.

Limitations of File Handling in C++

1. Error-Prone: File handling errors can crash programs.
2. Manual Cleanup: Need to explicitly close files.
3. Harder Debugging: Debugging file operations is more complex.
4. Data Corruption Risk: Improper writes can corrupt files.
5. Not Thread-Safe: Requires synchronization in multithreaded programs.