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引用定位

时间:2011-05-16 15:55:57  来源:站内  作者:潘春会

echo "---n";

$b = array(array());
var_dump(is_ref($b, $b)); //true
var_dump(is_ref($b, $b[0])); //false
echo "---n";

$b = array();
$b[] = $b;
var_dump(is_ref($b, $b)); //true
var_dump(is_ref($b, $b[0])); //false
var_dump(is_ref($b[0], $b[0][0])); //true*
echo "---n";

var_dump($a);
var_dump($b);

?>

* Please note the internal behaviour of PHP that seems to do the reference assignment BEFORE actually copying the variable!!! Thus you get an array containing a (different) recursive array for the last testcase, instead of an array containing an empty array as you could expect.

BenBE.

ludvig dot ericson at gmail dot com (28-Feb-2006 07:36)

 

For the sake of clarity:

$this is a PSEUDO VARIABLE - thus not a real variable. ZE treats is in other ways then normal variables, and that means that some advanced variable-things won't work on it (for obvious reasons):

<?php
class Test {
    var
$monkeys = 0;
   
    function
doFoobar() {
       
$var = "this";
        $
$var->monkeys++; // Will fail on this line.
   
}
}

$obj = new Test;
$obj->doFoobar
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