PHP empty() Function
The empty() function in PHP checks whether a variable is empty. It returns true if the variable has a value considered "empty," such as 0, null, false, an empty string, or an unset variable, and false otherwise.
Syntax
bool empty ( $var )Parameter:
This function accepts a single parameter as shown in above syntax and described below.
- $var: Variable to check whether it is empty or not.
Note: Below version of PHP 5.5, empty() only supports variables, anything other will result in a parse error. The following statement will not work empty(trim($var)). Instead, use trim($name) == false.
Return Value: It returns FALSE when $var exists and has a non-empty, non-zero value. Otherwise it returns TRUE. These values are considered to be as an empty value:
- "" (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)
Example: In this example we demonstrates the empty() function, which returns true for variables that are empty, such as 0, "0", NULL, false, empty arrays, empty strings, and undefined variables.
<?php
// PHP code to demonstrate working of empty() function
$var1 = 0;
$var2 = 0.0;
$var3 = "0";
$var4 = NULL;
$var5 = false;
$var6 = array();
$var7 = "";
// for value 0 as integer
empty($var1) ? print_r("True\n") : print_r("False\n");
// for value 0.0 as float
empty($var2) ? print_r("True\n") : print_r("False\n");
// for value 0 as string
empty($var3) ? print_r("True\n") : print_r("False\n");
// for value Null
empty($var4) ? print_r("True\n") : print_r("False\n");
// for value false
empty($var5) ? print_r("True\n") : print_r("False\n");
// for array
empty($var6) ? print_r("True\n") : print_r("False\n");
// for empty string
empty($var7) ? print_r("True\n") : print_r("False\n");
// for not declare $var8
empty($var8) ? print_r("True\n") : print_r("False\n");
?>
Output
True True True True True True True True
