Q8
What will be the output of the following PHP code?
A.
FALSE
B.
TRUE
C.
NULL
AnswerD.
ERROR
Answer: Option C
Solution
Answer: Option C
Solution:
There is an undocumented filter flag for FILTER_VALIDATE_BOOLEAN. The documentation implies that it will return NULL if the value doesn’t match the allowed true/false values. However this doesn’t happen unless you give it the FILTER_NULL_ON_FAILURE flag.