File Handling | Computer for GCSE/IGCSE - Year 11 PDF Download

Why Use Files?

• Files offer a permanent storage solution for data, allowing programs to access and modify it at a later time.
• Organized storage of data is facilitated by files, making it simpler to locate, access, and update information.
• Files support the sharing of data among different programs and users, enhancing collaboration and efficiency.
• Data backup is ensured by files, preventing data loss in the event of program or system shutdowns.
• Efficient storage and management of large volumes of data are made possible by files.
• Data can be easily transferred from one system to another using files.

Opening & Closing Files

• Common File Operations:
  • Opening: Establishes a connection between the file and the program.
  • Reading: Retrieves data from a file.
  • Writing: Saves new data to a file, overwriting existing content.
  • Appending: Adds new data to the end of a file without overwriting existing content.
  • Closing: Terminates the connection between the file and the program, freeing system resources.
• Types of Data:
  • Single items of data can be numbers, characters, or other basic data types.
  • A line of text usually ends with a newline character or an end-of-line marker.

Pseudocode example:

OPEN "file.txt"
filedata =  READ data
PRINT filedata
CLOSE file
OPEN "file.txt"
WRITE data
CLOSE file

Python example:

with open("file.txt", "r") as file:
    data = file.read()
    print(data)
with open("file.txt", "w") as file:
    file.write(data)

Java example:

    public static void main(String[] args) {
        String path = ("file.txt");
        try {
      FileReader f = new FileReader(path);
     BufferedReader reader = new BufferedReader(f);
            String data = reader.readLine();
   reader.close();
      BufferedWriter out = new BufferedWriter(f);
     out.write(data);
     out.close();
   } catch (Exception e) {
      System.err.println("No file found");
   }
}

Visual Basic example:

Dim File As New System.IO.StreamReader("file.txt")
Console.WriteLine(File.ReadLine())
File.Close()
Dim fileWrite As New System.IO.StreamWriter("file.txt")
fileWrite.WriteLine(data)
fileWrite.Close()