PHP fwrite(): Write to a File

The PHP fwrite() function is used when we need to write some content to a file. For example:

<?php
   $fp = fopen("myfile.txt", "w");
   fwrite($fp, "PHP is Fun!");
   fclose($fp);
?>

After executing the above PHP code, the content/text PHP is Fun! will get written in the file named myfile.txt.

Note: To write some text to a file, the file must be opened in w (writing) mode, using the function named fopen().

PHP fwrite() Syntax

The syntax of the fwrite() function in PHP is:

fwrite(filePointer, text, length)

The first two parameters (filePointer and text) are required, but the last one (length) is not (optional).

Note: The filePointer parameter specifies the pointer to the file.

Note: The text parameter is the content or text that has to be written in the file.

Note: The length parameter is used when we need to define the maximum number of bytes to write.

The fwrite() function returns the number of bytes (characters) written to the file. For example:

<?php
   $fp = fopen("myfile.txt", "w");
   if($fp)
   {
      echo fwrite($fp, "PHP is Fun! Isn't it?");
      fclose($fp);
   }
   else
      echo "<p>Unable to open the file</p>";
?>

Since the text PHP is Fun! Isn't it? is of 21 characters, therefore the output of the above PHP example on the fwrite() function should be:

PHP Write to File Line by Line using fwrite()

To write content to a file line by line using the PHP fwrite() function, use PHP_EOL as shown in the example given below:

<?php
   $fp = fopen("myfile.txt", "w");
   if($fp)
   {
      $line = "Hey,";
      fwrite($fp, $line.PHP_EOL);
      
      $line = "What's going on?";
      fwrite($fp, $line.PHP_EOL);
      
      $line = "Is everything alright?";
      fwrite($fp, $line.PHP_EOL);
      fclose($fp);
   }
   else
      echo "<p>Unable to open the file</p>";
?>

The three texts will be written line by line. Therefore, after executing the above PHP example, here is the snapshot of the file myfile.txt.

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