Can I assign a value to a $_POST variable in PHP?

Question

For example, I am using a $_POST variable to insert data into a DB. Just before this query I have a few tests and if they are true I want to adjust that (hidden) $_POST value.

Ex.

if($baby_dragon_eats_children){
  $_POST['hidden_value'] = "grapes";
}

Can $_POST['hidden_value'] be assigned a new value and then be passed to another function as $_POST and be able to access the new $_POST['hidden_value']?

Thanks

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$_POST['consolidate_answers']

• IF you assign a value to $_POST you should document is very clearly as it is not common nor considered "best" practice.
• IF you have any extensions of PHP such as Suhosin Patch... it may block such actions..
• Handle your own arrays, don't depend on $_POST!
• IF need be, make a copy of $_POST and work with that.

Answer 1

You can assign values to $_POST, but if you do so you should document it very clearly with comments both at the point of assignment and the later point of access. Manually manipulating $_POST can break future programmers' (including your own) expectations of what is in the superglobal and where it came from.

There may be other alternatives, like:

$my_post = $_POST;
$my_post['hidden_value'] = 12345;

// In a function:
function func() {
   // Emulate a superglobal
   echo $GLOBALS['mypost']['hidden_value'];
}

Answer 2

Can $_POST['hidden_value'] be assigned a new value and then be passed to another function as $_POST and be able to access the new $_POST['hidden_value']?

It can in normal PHP.

However, extensions like the Suhosin Patch may block this.

Also, it feels wrong in general. $_POST is intended to contain the raw, incoming POST data - nothing else. It should not be modified IMO.

A better way to go would be to fetch all the data you plan to insert into the database into an array, and do the manipulations in that array instead.