boolean: Converting to boolean

To explicitly convert a value to boolean, use the (bool) or (boolean) casts.

In most cases the cast is unnecessary, since a value will be automatically converted if an operator, function or control structure requires a boolean argument.

<?php
var_dump((bool) "");        // bool(false)
var_dump((bool) 1);         // bool(true)
var_dump((bool) -2);        // bool(true)
var_dump((bool) "foo");     // bool(true)
var_dump((bool) 2.3e5);     // bool(true)
var_dump((bool) array(12)); // bool(true)
var_dump((bool) array());   // bool(false)
var_dump((bool) "false");   // bool(true)
?>

• The boolean FALSE itself.
• The integer 0 (zero).
• The float 0.0 (zero).
• The empty string, and the string "0".
• An array with zero elements.
• The special type NULL (including unset variables).
• SimpleXML objects created from empty tags.