In this case can I use # to avoid useless isset()? - php

Question

Basically I need to create a string with $_GET['param'], something like:
$myString = $_GET['param'] . 'abc';
When $_GET['param'] isn't isset i am perfectly fine with $myString being just ='abc'
So I can do something like this:
$myString = #$_GET['param'] . 'abc';
Or use the standard way with isset:
if (!isset($_GET['param']))
$_GET['param'] = '';
$myString = $_GET['param'] . 'abc';
In this case using the # suppresser is considering such a bad pratice?

Answer 1

The most elegant thing IMHO would be to wrap that in a nice getter function, something like:
function _getParam($param, $default = '') {
if (!isset($_GET[$param]))
return $default;
return $_GET[$param];
}
$myString = _getParam('param').'abc';
yes123 note:
As dvir said having a getter function for input variables in your framework can be handy. But this _getParam suffers of this problem:
Let's see we make a typo in our code, we want to access $_GET['param'] and istead of it we type:
_getParam('parm')
Our code will work without generting any problems and we will have hard time finding the error.
So I thought we could modify the function presented to something like:
function _get() {
$key = func_get_arg(0);
if (func_num_args()==2) {
if (!isset($_GET[$key]))
return func_get_arg(1);
}
return $_GET[$key];
}
This ensures that when we typo it with _get('parm') we will get a notice throwed normally. But when we use it with 2 param we get out default value:
_get('param','myDefaultValue');

Answer 2

You can avoid using # like this:
$myString = ( isset($_GET['param']) ? $_GET['param'] : '' ) . 'abc';
In this case using the # suppresser is considering such a bad pratice?
Generally from the developer perspective it is good idea to avoid using # operator because it may hide errors that may be useful when debugging a particular problem. Other than that, it is very slow and for that reason, in the future version of PHP, # won't be supported in ini_set calls.

Answer 3

It's not extremely elegant in my opinion (although it is short). I think the worst thing you have going here may be writing to the $_GET superglobal directly in your "standard" approach.
if (!isset($_GET['param'])) $_GET['param'] = '';
Maybe I'm being paranoid, but another unrelated script could run afterwards that checks for isset($_GET['param']), and now it will return TRUE because you injected '' into it.
So, yes - you can safely use error suppression here (there's not much you're going to miss), but there's no reason to avoid isset() either:
$myString = isset($_GET['param']) ? $_GET['param'] : '' . 'abc';