boolean variable values in PHP to javascript implementation [duplicate]

Question

I've run into an odd issue in a PHP script that I'm writing-- I'm sure there's an easy answer but I'm not seeing it.

I'm pulling some vars from a DB using PHP, then passing those values into a Javascript that is getting built dynamically in PHP. Something like this:

$myvar = (bool) $db_return->myvar;  $js = "<script type=text/javascript>         var myvar = " . $myvar . ";         var myurl = 'http://someserver.com/ajaxpage.php?urlvar=myvar';        </script>"; 

The problem is that if the boolean value in the DB for "myvar" is false, then the instance of myvar in the $js is null, not false, and this is breaking the script.

Is there a way to properly pass the value false into the myvar variable?

Thanks!

Answer 1

use json_encode(). It'll convert from native PHP types to native Javascript types:

var myvar = <?php echo json_encode($my_var); ?>; 

and will also take care of any escaping necessary to turn that into valid javascript.

Answer 2

This is the simplest solution:

Just use var_export($myvar) instead of $myvar in $js;

$js = "<script type=text/javascript>         var myvar = " . var_export($myvar) . ";         var myurl = 'http://someserver.com/ajaxpage.php?urlvar=myvar';        </script>"; 

Note: var_export() is compatible with PHP 4.2.0+