In php, is 0 treated as empty?

Question

Code will explain more:

$var = 0;  if (!empty($var)){ echo "Its not empty"; } else { echo "Its empty"; } 

The result returns "Its empty". I thought empty() will check if I already set the variable and have value inside. Why it returns "Its empty"??

Answer 1

http://php.net/empty

The following things are considered to be empty:

• "" (an empty string)
• 0 (0 as an integer)
• 0.0 (0 as a float)
• "0" (0 as a string)
• NULL
• FALSE
• array() (an empty array)
• var $var; (a variable declared, but without a value in a class)

Note that this is exactly the same list as for a coercion to Boolean false. empty is simply !isset($var) || !$var. Try isset instead.

Answer 2

I was wondering why nobody suggested the extremely handy Type comparison table. It answers every question about the common functions and compare operators.

A snippet:

Expression      | empty($x) ----------------+-------- $x = "";        | true     $x = null       | true     var $x;         | true     $x is undefined | true     $x = array();   | true     $x = false;     | true     $x = true;      | false    $x = 1;         | false    $x = 42;        | false    $x = 0;         | true     $x = -1;        | false    $x = "1";       | false    $x = "0";       | true     $x = "-1";      | false    $x = "php";     | false    $x = "true";    | false    $x = "false";   | false    

Along other cheatsheets, I always keep a hardcopy of this table on my desk in case I'm not sure