Say I have a function called set_session_variable that looks like:
function set_session_variable($name, $value) {
// ...write value to the specified path
}
How would I write this function (without using an eval) so that I can do something like:
set_session_variable('foo', 'bar'); // Would set $_SESSION['foo'] = 'bar';
set_session_variable('foo[bar][baz]', 'blah'); // Would set $_SESSION['foo']['bar']['baz'] = 'blah';
I highly suggest, that you won't use
set_session_variable('foo[bar][baz]', 'blah');
but instead
set_session_variable('foo', array('bar'=>array('baz' => 'blah')));
Additionally, you don't need a function call for that at all:
$_SESSION['foo']['bar']['baz'] = 'blah';
You can change the implementation of $_SESSION with the session save handler.
If you're only concerned how you could parse a string like 'foo[bar][baz]', this has been asked before, for example use strings to access (potentially large) multidimensional arrays.
$_SESSION in there, I'm pretty sure). Anyway, you see the second example-line of code and the linked question/answer. Both should fit your needs.A more relevant question is why you need a function at all. Function calls have a cost, and the function doesn't appear to do useful work.
Example assignments:
$_SESSION['foo'] = 'bar';
$_SESSION['foo']['bar']['baz'] = 'blah';
$foo['bar']['baz'] = 'blah';
$_SESSION['foo'] = $foo;
In direct answer to your question: You could parse the value of $name within set_session_variable() using the PCRE module and a regular expression.
Even simpler and faster would be parsing it with sscanf() provided you are able and willing to impose a convention on the naming of array keys.
A cleaner alternative function:
$array['bar']['baz'] = 'blah';
set_session_variable('foo', $array);
function set_session_variable($key, $val) {
$_SESSION[$key] = $val;
}
One way to solve this is to mimic function overloading, example in this post -> PHP function overloading
Another way is to add one string argument to your function, with your array indices delimited. For example: set_session_variable('foo', 'bar', 'baz;key'); Which saves the value 'bar' into foo['baz']['key'].
All you have to do is tear the 3rd argument apart (i use ; as delimiter here).
foois a string. Next you setfoo[bar][baz]to blah. What behaviour do you expect at this point? Do you want to convertfoofrom string to array (such thatfoo[bar][blaz]has value blah)? Or $_SESSION['foo'] gives you array such that $_SESSION['foo']['bar']['baz'] == 'blah?