What is the difference between empty and is_null? _PHP Tutorial

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Release: 2016-07-13 10:54:56
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What is the difference between empty and is_null?

bool empty ( mixed $var )

If var is a non-empty or non-zero value, empty() returns FALSE. In other words, "", 0, "0", NULL, FALSE, array(), var $var; and objects without any properties will be considered empty, and TRUE is returned if var is empty.

empty() is the antonym of (boolean) var except that it does not produce a warning when the variable is not set. See Converting to Boolean for more information.
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A variable is considered NULL in the following situations:

bool is_null ( mixed $var )

Returns TRUE if var is null, FALSE otherwise.


is assigned the value NULL.

has not been assigned a value yet.

is unset().

www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/632272.htmlTechArticleWhat is the difference between empty and is_null? bool empty ( mixed $var ) empty() returns FALSE if var is a non-empty or non-zero value. In other words, 0, 0, NULL, FALSE, array(), va...
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