这是测试已发布变量存在的正确方法吗？

Question

If a query maybe be optionally run as a get() or a post(), so that $id = $_POST['id'] maybe get a null value, are any of these a good practice way to test for the possibly posted variable's existence.

if (!empty($_POST['id'])){ $id = $_POST['id'];}else{$id = FALSE;}

if (isset($_POST['id'])){ $id = $_POST['id'];}else{$id = FALSE;}

$id = isset($_POST['id']) ? $_POST['id'] : FALSE;

or is there some other preferred method? They all do a $_REQUEST() twice which inclines me to think there could be a better way.

Thanks!

Answer 1

I would go with:

$id = isset($_POST['id']) && strlen($_POST['id']) > 0 ? (int)$_POST['id'] : FALSE;

First it checkes if the var is set, and then check if the length is longer than 0.

In my opinion it is the best readable, as you dont need 5 lines of code if you indent it correctly, what makes it harder to read and makes your file longer:

 if (isset($_POST['id'])){ 
   $id = $_POST['id'];
 }else{
   $id = FALSE;
 }

And if you use $_POST for a simple thing as an ID, just cast it to an int with (int)$_POST['id']. That way you are sure to have a number.