Cast object to array - strange behaviour [duplicate]

问题

I am casting an object to array and after that I am unable to access the resulting array by a key.

This is the code

print_r($new);
$new = (array)$new;
echo $new['EPPContactemail'];

foreach($new as $attr=>$value)
{
    echo "$attr => $value \n";
}

And the output is

EPPContact Object
(
    [id:EPPContact:private] => 6553377C74FC9899
    [roid:EPPContact:private] => 50085436-UK
    [status:EPPContact:private] => ok
    [voice:EPPContact:private] => +44.554545454
    [email:EPPContact:private] => some@email.com
    [fax:EPPContact:private] => 
    [clID:EPPContact:private] => TSOHOST
    [crID:EPPContact:private] => EPP-TSOHOST
    [crDate:EPPContact:private] => 2013-07-17T09:53:41
)

Notice: Undefined index: EPPContactemail in /home/parvhraban/domains/src/local_libs/EPP/Builder/Contact/Update.php on line 9
EPPContactid => 6553377C74FC9899
EPPContactroid => 50085436-UK
EPPContactstatus => ok
EPPContactvoice => +44.554545454
EPPContactemail => some@email.com
EPPContactfax => 
EPPContactclID => TSOHOST
EPPContactcrID => EPP-TSOHOST
EPPContactcrDate => 2013-07-17T09:53:41

I can clearly see that EPPContactemail key exists and holds the value although when accessing it (line 3, echo statement) it throws an error of undefined index.

Could you please explain me what causes this behaviour?

回答1:

When casting an object to an array, certain properties (private, protected and parent properties) are assigned to the array, with keys that look like:

*protected
ClassNamePrivate
ParentNameProperty

But they really look like this:

"\0*\0protected"
"\0ClassName\0Private"
"\0ParentName\0Property"

That's what's causing your problems here.
Replace:

echo $new['EPPContactemail'];

with

echo $new["\0EPPContact\0email"];

And take it from there.
Note that you'll have to use double quotes as string delemiters, because '\0' !== "\0", just as '\n' !== "\n"

This behaviour is documented on php.net, though it's rather well hidden

来源：https://stackoverflow.com/questions/17695490/cast-object-to-array-strange-behaviour

标签

php

arrays

casting