User:Ottomata/PHP False
Value | boolean | isset() | empty() |
---|---|---|---|
NULL | false | false | true |
FALSE | false | true | true |
'' | false | true | true |
0 | false | true | true |
'0' | false | true | true |
'0000' | true | true | false |
array() | false | true | true |
First the output:
NULL == false isset(NULL) == false empty(NULL) == true false == false isset(false) == true empty(false) == true '' == false isset('') == true empty('') == true 0 == false isset(0) == true empty(0) == true '0' == false isset('0') == true empty('0') == true '0000' == true isset('0000') == true empty('0000') == false array() == false isset(array()) == true empty(array()) == true
And here's the code to output this:
<?php
$values = array(
NULL,
FALSE,
'',
0,
'0',
'0000',
array(),
);
foreach ($values as $value)
{
if (is_array($value))
$v = 'array()';
else
$v = var_export($value, true);
if ($value) {
$conditional = 'true';
}
else {
$conditional = 'false';
}
$isset = var_export(isset($value), true);
$empty = var_export(empty($value), true);
printf("%-14s == %s\n%-14s == %s\n%-14s == %s\n\n", $v, $conditional, "isset($v)", $isset, "empty($v)", $empty);
}
?>