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Variable function library: empty

Source: Internet
Author: User
Keywords empty php Chinese function manual variable function library
Tags aliyun example function function library html http note php
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Empty

(unknown)

Empty---&http://www.aliyun.com/zixun/aggregation/37954.html ">nbsp; Determine whether a variable is set

Syntax: int empty (mixed Var);

Description:

Returns TRUE if the variable exists and has a set variable value return FALSE.

Example:

<?php

$var = 0;

if (empty ($var)) {#evaluates true

print ' $var is either 0 or not on all set ';

}

if (!isset ($var)) {//Evaluates false

print ' The $var is isn't set at all ';

}

?>

Note: It is meaningless to use anything that is not a variable. For example: Empty (Addslashes ($name)) is meaningless.

Reference: Isset () unset ()

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