Weird behavior of matching array keys after json_decode()
- by arnorhs
I've got some very weird behavior in my PHP code. I don't know if this is actually a good SO question, since it almost looks like a bug in PHP. I had this problem in a project of mine and isolated the problem:
// json object that will be converted into an array
$json = '{"5":"88"}';
$jsonvar = (array) json_decode($json); // notice: Casting to an array
// Displaying the array:
var_dump($jsonvar);
// Testing if the key is there
var_dump(isset($jsonvar["5"]));
var_dump(isset($jsonvar[5]));
That code outputs the following:
array(1) {
["5"]=>
string(2) "88"
}
bool(false)
bool(false)
The big problem: Both of those tests should produce bool(true) - if you create the same array using regular php arrays, this is what you'll see:
// Let's create a similar PHP array in a regular manner:
$phparr = array("5" => "88");
// Displaying the array:
var_dump($phparr);
// Testing if the key is there
var_dump(isset($phparr["5"]));
var_dump(isset($phparr[5]));
The output of that:
array(1) {
[5]=>
string(2) "88"
}
bool(true)
bool(true)
So this doesn't really make sense. I've tested this on two different installations of PHP/apache.
You can copy-paste the code to a php file yourself to test it.
It must have something to do with the casting from an object to an array.