Example Analysis of null judgement assignment in PHP

Editor to share with you the example analysis of null judgment assignment in PHP, I believe that most people do not know much about it, so share this article for your reference. I hope you will gain a lot after reading this article. Let's learn about it together.

Several Writing methods of null judgment assignment

/ when $an is not null, $b = $a, otherwise $b = 233333. / / Mode 1: $b = $an or $b = 233333; Mode 2: $b = $a? $a: 23333X / Mode 3$ b = $a?: 233333, PHP7 $b = $a?? 233333

Pay attention to the difference between mode 3 and mode 4, and make clear what you want to judge. In addition to mode 4, the other three can also judge the situation of false,'','0',0, [].

The above is all the contents of the article "sample Analysis of null judgment assignment in PHP". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!