syntax explanation

Hangin' Around Joined: May 31, 2006 Posts: 49

Hi,

Can someone give me an explanation of the following in terms of the format?

Code:




$start = ( isset($HTTP_GET_VARS['start']) ) ? intval($HTTP_GET_VARS['start']) : 0;

What is the use of the ? and the : here and does php.ini effect how you should use them? I saw something somewhere about rewriting statements like this differently but I don't understand the use of the question mark in this context.

Any help appreciated.

registered · Site Admin Joined: Jun 04, 2004 Posts: 6437

Basically, it's like an IF statement, and it's called a Only registered users can see links on this board! Get registered or login!. The statement above could be written like this and it would have the same result:

Code:

if (isset($HTTP_GET_VARS['start']) ) {


  $start = intval($HTTP_GET_VARS['start']);


} else {


  $start = 0;


}

According to the documentation, for:

Code:

$first ? $second : $third

Quote:

If the value of the first subexpression is TRUE (non-zero), then the second subexpression is evaluated, and that is the result of the conditional expression. Otherwise, the third subexpression is evaluated, and that is the value.

To answer your specific question, the format of $start is an integer.