Pass a value into filter_input() using variable

Question

Can anyone please explain, why do I get very strange warning:

filter_input() expects parameter 1 to be long, string given

when executing the co

Answer 1

Here the problem. When you concatenate 'INPUT_' with variable it bacame a string, see example:

echo $type = 'INPUT_' . 'POST'; // give you a string INPUT_POST

echo INPUT_POST; //give you 0

That's why :

filter_input() expects parameter 1 to be long, string given