Reading and writing files

Writing to a File:

• fopen() → Opens a file.
• fwrite() → Writes data into the file.
• fclose() → Closes the file.

Example:

<?php
// Open file in write mode ("w") - if file doesn’t exist, it will create one
$file = fopen("example.txt", "w");

// Write some content
fwrite($file, "Hello, this is my first file handling example in PHP!");

// Close the file
fclose($file);

echo "Data written to file successfully!";
?>

Output:

After running, a file example.txt will be created with your text inside.

2. Reading from a File:

• fopen() → Opens file.
• fread() → Reads file content.
• filesize() → Gets file size (to read full file).
• fclose() → Close the file.

Example:

<?php
// Open file in read mode ("r")
$file = fopen("example.txt", "r");

// Read content (need file size)
$content = fread($file, filesize("example.txt"));

// Close the file
fclose($file);

echo "File Content: " . $content;
?>

Output:

File Content: Hello, this is my first file handling example in PHP!

Modes in fopen():

• "r" → Read only (file must exist).
• "w" → Write only (creates new file, erases old content).
• "a" → Append (write from end of file, keeps old content).
• "r+" → Read and write.
• "w+" → Read and write (overwrites file).
• "a+" → Read and write (append mode).