这是什么表达方式？ [重复]

Question

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• Reference — What does this symbol mean in PHP? 18 answers

i'm noob with php and i was wondering what that expression mean:

$extra_adults = ($num_adults > $people) ? $num_adults-$people : 0; 

can someone explain me please?

Thank you very much for your time.

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Answer 1

Its a Ternary operator statement. E.g.

$x = $valid ? 'yes' : 'no';

It will assign yes to $x if $valid is true and no if $valid is false.

So, as per your statement which is:

$extra_adults = ($num_adults > $people) ? $num_adults-$people : 0; 

If $num_adults is greater than $people then it will do $num_adults -$people and assing the result to $extra_adults, else it will assign 0 to $extra_adults.