Question

This example is from php.net:

<?php function Test() {     static $a = 0;     echo $a;     $a++; } ?> 

And this is my code:

function getNextQuestionID() {     static $idx = 0;     return $idx++; } 

And I use it in JavaScript:

'quizID=' + '<?php echo getNextQuestionID(); ?>' 

Returns 0 everytime. Why?

Answer 1

I believe you misunderstand what static vars do. Try this code and you may understand better:

echo getNextQuestionID() . ', ' getNextQuestionID() . ', ' getNextQuestionID(); 

And you will see what I mean.

The static var only lives as long as the script does.

The reason it is returning 0 on the first run instead of 1 is because you are using the postfix operator $var++ instead of the prefix version – ++$var. The difference is is that the increment only gets applied when using the postfix operator after the function returns – but if you use the prefix operator it is applied before the function returns.