Using PHP's file() Function to Read Files into an Array

PHP provides a convenient built‑in function array file ( string $filename [, int $flags = 0 [, resource $context ]] ) that reads an entire file and returns its contents as an array, where each line becomes an element.

To illustrate, create a file named sample.txt with the following content:

<code>Hello, world!
This is a sample file.
It is used for testing file functions in PHP.
</code>

Calling the function without any flags reads the file and retains the line‑ending characters:

<code>$fileContent = file("sample.txt");
print_r($fileContent);
</code>

The resulting array looks like:

<code>Array
(
    [0] => Hello, world!
    [1] => This is a sample file.
    [2] => It is used for testing file functions in PHP.
)
</code>

If you do not want the newline characters, pass the FILE_IGNORE_NEW_LINES flag:

<code>$fileContent = file("sample.txt", FILE_IGNORE_NEW_LINES);
print_r($fileContent);
</code>

The output is the same array but without the trailing newlines.

To also skip empty lines, combine FILE_IGNORE_NEW_LINES with FILE_SKIP_EMPTY_LINES :

<code>$fileContent = file("sample.txt", FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
print_r($fileContent);
</code>

This call removes both the newline characters and any blank lines, leaving only the non‑empty lines in the array.

In summary, the file() function offers a flexible way to read files into arrays, and its optional flags let you control newline retention and empty‑line filtering to suit various file‑processing needs.