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copied!<p>PHP provides <a href="http://php.net/manual/en/array.sorting.php" rel="nofollow">quite a few functions for sorting arrays</a>. In this case, the one you want is <a href="http://php.net/uasort" rel="nofollow"><code>uasort()</code></a>, which sorts an array according to a user-defined comparison function while maintaining key-value associations:</p> <pre><code>function compare_results ( $a, $b ) { $diff = strcmp( $a['test_user_data']['user_status'], $b['test_user_data']['user_status'] ); if ( $diff != 0 ) return $diff < 0 ? -1 : 1; // ascending order // ("Attempted" < "Not attempted") $diff = $a['test_result_data']['total_obtained_marks'] - $b['test_result_data']['total_obtained_marks']; if ( $diff != 0 ) return $diff > 0 ? -1 : 1; // descending order $diff = $a['test_result_data']['no_wrong_answers'] - $b['test_result_data']['no_wrong_answers']; if ( $diff != 0 ) return $diff < 0 ? -1 : 1; // ascending order $diff = strcmp( $a['test_user_data']['test_user_time_used'], $b['test_user_data']['test_user_time_used'] ); if ( $diff != 0 ) return $diff < 0 ? -1 : 1; // ascending order $diff = strcmp( $a['test_user_data']['user_name'], $b['test_user_data']['user_name'] ); if ( $diff != 0 ) return $diff < 0 ? -1 : 1; // ascending order return 0; // give up, they're as good as equal } uasort( $test_result, compare_results ); </code></pre> <p>Writing such comparison functions is (briefly) documented on the <a href="http://php.net/uasort" rel="nofollow"><code>usort()</code></a> function documentation page.</p> <p>Note, in particular, the warning about non-integer return values being truncated, which is why I'm returning <code>$diff < 0 ? -1 : 1</code> rather than just <code>$diff</code> itself. In your case, this <em>shouldn't</em> matter, since the numeric values appear to be integers, but it could cause hard-to-find bugs if the system was ever modified to allow, say, partial marks to be awarded. Thus, always returning either -1, 0 or 1 from comparison functions is a good habit to get into.</p> <p>(For the string comparisons, the <code>$diff < 0 ? -1 : 1</code> is doubly pointless, since <a href="http://php.net/strcmp" rel="nofollow"><code>strcmp()</code></a> is documented to always return -1, 0 or 1 anyway, but I've used it there also for the sake of consistency. It doesn't really do any harm, and as I said, it's a good habit to get into.)</p> <p>Also note that I'm comparing the time values as strings. If this does not yield the results you're expecting, you'll need to write your own time comparison code.</p> <p>Ps. If you're using PHP 5.3.0 or later, you can also write the comparison function as an <a href="http://php.net/manual/en/functions.anonymous.php" rel="nofollow">anonymous function</a>, like this:</p> <pre><code>uasort( $test_result, function ( $a, $b ) { // function body goes here } ); </code></pre>

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