3v4l.org

run code in 300+ PHP versions simultaneously
<?php $query_string = [ 'one' => 1, 'two' => '', 'three' => null, // gets omitted 'four' => ' ', // gets encoded 'five' => "&test=test" // gets encoded ]; echo http_build_query($query_string); echo "\n---\n"; echo http_build_query($query_string, '', '&amp;'); echo "\n\n\n\n\n";

preferences:
56.28 ms | 402 KiB | 5 Q