Fury-Tech Logo
Home  News  Articles  Reviews  Guides  Resources  Forums 
Fury-Tech // Technology news, hardware and game reviews, guides, articles, and resources   
Search:



There are currently 0 members and 29 guests browsing on Fury-Tech.

SEO Scripts
SEO Scripts
List Cleaner Script
Keyword Cleaner
Directory Script
Directory Script
BidVerve Directory
BidVerve Directory
Directory Grow
Directory Grow


Join our community in the tech forums for uncut technology discussion.

empty


(PHP 3, PHP 4, PHP 5 )

empty -- Determine whether a variable is empty

Description

bool empty ( mixed var )

Determine whether a variable is considered to be empty.

Parameters

var

Variable to be checked

Note: empty() only checks variables as anything else will result in a parse error. In other words, the following will not work: empty(trim($name)).

empty() is the opposite of (boolean) var, except that no warning is generated when the variable is not set.

Return Values

Returns FALSE if var has a non-empty and non-zero value.

The following things are considered to be empty:

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

ChangeLog

VersionDescription
PHP 5

As of PHP 5, objects with no properties are no longer considered empty.

PHP 4

As of PHP 4, The string value "0" is considered empty.

Examples

Example 1. A simple empty() / isset() comparison.

<?php
$var
= 0;

// Evaluates to true because $var is empty
if (empty($var)) {
    echo
'$var is either 0, empty, or not set at all';
}

// Evaluates as true because $var is set
if (isset($var)) {
    echo
'$var is set even though it is empty';
}
?>

Notes

Note: Because this is a language construct and not a function, it cannot be called using variable functions

Join our community in the tech forums for uncut technology discussion.



©2007 Fury-Tech | Tech News, Hardware Reviews, Forums, Guides, and more.

Web Hosting by Intavant

Tech News | Articles | Reviews | Guides | Resources | Tech Forums