This article mainly shares with you several methods of determining whether a variable is empty in PHP. I hope it can help you. Whether it is empty method

This article mainly shares with you several PHP methods to determine whether a variable is empty. I hope it can help you.

• Use if()

$a=1;if($a)     值为true$a='a';
if($a)     值为true$a='';
if($a)     值为false$a=0;
if($a)     值为false$a=null;
if($a)     值为false

• empty

$a=1;if(!empty($a))     值为true$a='a';
if(!empty($a))     值为true$a='';
if(!empty($a))     值为false$a=0;
if(!empty($a))     值为false$a=null;
if(!empty($a))     值为false

• Comparison of several other functions
  

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