How to use php empty function

The empty() function is a built-in function in PHP used to check whether a variable is empty. The syntax is empty (var), which returns FALSE when var exists and has a non-empty non-zero value, otherwise it returns TRUE.

How to use php empty() function?

empty() function is used to check whether a variable is empty.

Syntax:

empty (var)

Parameters: This function accepts a single parameter, as shown in the above syntax

● var: Variable to check if it is empty.

Return value: Returns FALSE when var exists and has a non-empty, non-zero value. Otherwise returns TRUE.

empty() Determines whether a variable is considered empty. When a variable does not exist, or its value is equal to FALSE, then it is considered not to exist. empty() does not generate a warning if the variable does not exist.

Note: PHP 5.5 version supports expressions, not just variables. Under PHP 5.5, empty() only supports variables, anything else will cause a parsing error. The following statement will not work (trim(var)). Instead, use trim(name) == false.

Version requirements: PHP 4, PHP 5, PHP 7

These values ​​are considered null values:

●　"" (empty string )

●　0 (0 is an integer)

● 0.0 (0 is a floating point number)

● “0” (0 is a string)

● NULL

● FALSE

● array() (an empty array)

Let’s take an example to see how to use the php empty() function.

<?php 
$var1 = 0; 
$var2 = 0.0; 
$var3 = "0"; 
$var4 = NULL; 
$var5 = false; 
$var6 = array(); 
$var7 = ""; 

empty($var1) ? print_r("True\n") : print_r("False\n"); 
empty($var2) ? print_r("True\n") : print_r("False\n"); 
empty($var3) ? print_r("True\n") : print_r("False\n"); 
empty($var4) ? print_r("True\n") : print_r("False\n"); 
empty($var5) ? print_r("True\n") : print_r("False\n"); 
empty($var6) ? print_r("True\n") : print_r("False\n"); 
empty($var7) ? print_r("True\n") : print_r("False\n"); 
empty($var8) ? print_r("True\n") : print_r("False\n"); 
  
?>

Output:

True
True
True
True
True
True
True
True

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