Notice: Only variables should be passed by reference

You are getting this error when you passed array value in the function. Often developers end up their code with this error:

Notice: Only variables should be passed by reference in D:\xampp\htdocs\xxx\abc.php on line 9

Why these errors occur?

If you are passing a real variable into the function, you could get this error. Because only actual variable may be passed by reference.

See below code:

$fileName  = ‘This-is-a-testing-string’;

$result = end(explode('-', $fileName));

echo $result;

With above code you will get this error “Notice: Only variables should be passed by reference”.

Because the end() function requires a reference, it modifies the internal representation of the array.

And explode('-', $file_name) cannot be turned into a reference. PHP language doesn’t allow this. PHP language has restricted this.

So you have to use below code instead of above

$fileName  = ‘This-is-a-testing-string’;

$expFileName = explode('-', $fileName);

$result  = end($expFileName);

echo $result;