Reading and Writing Files
Explore how to read data using token-based and line-based methods and write formatted output to files in C++. Understand file open modes to control file access, including appending and overwriting, and learn the basics of buffered file I/O to manage resources effectively.
In the previous lesson, we learned how to open and close file streams, establishing a connection between our program and the file system. However, a connection alone doesn't get the work done. To save game progress, generate reports, or load configuration settings, we must transfer data across that connection. In this lesson, we will start by reading text from files, then we will write text back to files, and control file behavior using open modes.
Reading data: Tokens vs. lines
When reading text files, we generally use two strategies: token-based reading and line-based reading. Choosing the right one depends on how our data is structured.
Formatted extraction (>>)
The extraction operator (>>) is "token-based." It skips leading whitespace (spaces, tabs, newlines) and reads characters until it hits the next whitespace. This is ideal for reading specific data types, such as numbers or single words.
Here ...