Read consecutive lines from file into key => value array - php

Question

I am trying to convert a user/pass txt file to an array, I tried to do this with a foreach, explode, reg_split, but didn't get anything working in the right way.
Also a blank line should be skipped...
Example text file:
username1
password1
username2
password2
username3
password4
Example array:
array(
$username1 => $password1,
$username2 => $password2
)

Answer 1

Create an array of pairs from the consecutive lines, then combine the column of keys with the column of values:
$chunks = array_chunk(
file('userpass.txt', FILE_SKIP_EMPTY_LINES|FILE_IGNORE_NEW_LINES),
2
);
$users = array_combine(
array_column($chunks, 0),
array_column($chunks, 1)
);
Explanation
$chunks is an array of arrays: each inner array has two elements: #0 is the username (first line) and #1 is the password (second line). Using file to skip blank lines and remove trailing new-lines keeps this code simple, but not bullet-proof.
$users then is made by taking all the usernames (index 0 from all the inner arrays) and pointing them to all the passwords (index 1).
You can accomplish the same with a loop over $chunks. However, I prefer this approach because all looping is handled inside the engine, where it is marginally more performant.

Answer 2

Split the file into one array and then combine them into a new array with key-value pairs
$file = file("usernames.txt", FILE_SKIP_EMPTY_LINES|FILE_IGNORE_NEW_LINES);
$array = [];
for($i = 0; $i < count($file) - 1; $i++){
$array[$file[$i]] = $file[$i + 1];
}

Answer 3

I have to think on it, but I know you can read the file into an array using php's file() method.
$var = file("myFile.txt", FILE_SKIP_EMPTY_LINES);