In one of PHP questions on assessmentee.com, following code:
$a = "";
echo gettype($a);
echo empty($a);
echo is_null($a);
echo isset($x);
returns only "string1"
Why don't we have three bolean values returned, one for each of three functions: empty(), is_null() and isset()?
echo gettype($a); // outputs "string"
echo empty($a); // outputs true, in your environment this is 1
echo is_null($a); // outputs false, "" isn't null, in your environment this is probably blank
echo isset($x); // outputs false, in your environment this is probably blank
You get all the results :string, true, false & false
echo gettype($a); // outputs "string"
echo empty($a); // outputs 1 (true)
echo is_null($a); // outputs false, or "" in echo
echo isset($x); // outputs false, or "" in echo
Your could try running it this way to see the different resuls:
echo gettype($a),'-',empty($a),'-',is_null($a),'-',isset($x),'-';
output: string-1---
echo gettype($a); // Outputs a "string" because the datatype used is a string
echo empty($a); // Outputs true, because the criteria that it is an empty string
echo is_null($a); // Outputs false, "" isn't null, this is probably blank
echo isset($x); // Outputs false because isset means "is set"
echoprints to string.false,true,nullare not represented as strings, I can't find right now something to share with you explaining it, but you could also usevar_dump.