哪个会更快，哪个是正确的PHP，而if和integer呢？

Question

I have 2 while loops in an if then else if statement, the code works and all is good, but just a little question.

Take my first example, I declare on the while loop the true statement for it to execute,

if ($levelChange > 0) {
    while ($levelChange != 0) {
        echo '<p>You gained a level you are now ' . ($levelChange + $user['level']) . '</p>';
        $levelChange--;
    }
}
elseif ($levelChange < 0) {
    while ($levelChange != 0) {
        echo '<p>You just lost a level you are now ' . ($levelChange + $user['level']) . '</p>';
        $levelChange++;
    }
}

And my second example I don't,

if ($levelChange > 0) {
    while ($levelChange) {
        echo '<p>You gained a level you are now ' . ($levelChange + $user['level']) . '</p>';
        $levelChange--;
    }
}
elseif ($levelChange < 0) {
    while ($levelChange) {
        echo '<p>You just lost a level you are now ' . ($levelChange + $user['level']) . '</p>';
        $levelChange++;
    }
}

They both work but which one is better to use and why, also if anyone knows which could be faster please enlighten me,

Thanks

Answer 1

PHP converts its arguments to boolean values where a conditional statement is expected. For numbers every non-zero value ( != 0 ) evaluates to true. The PHP docs for the boolean type have a table with conversion rules for different types.

Therefore, if($x) is equivalent to if($x == TRUE) . There isn't any (measurable) performance difference between the two forms.

Answer 2

In this case I would say it's your preference. I would probably use the comparison to 0, but that is just my preference because it is slightly more verbose to someone else reading your code. There shouldn't be much a change in performance either way.