Null checking php

Connect and share knowledge within a single location that is structured and easy to search. The table also shows some tricky values regarding the null comparison. No it's not a bug. There you can see that an empty string "" compared with false , 0 , NULL or "" will yield true. This is not a bug but PHP normal behavior. To study in deep this difference, please read the official documentation.

NULL stands for a variable without value. Both ways, however, generate a warning if the variable is not defined. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?

Collectives on Stack Overflow. Learn more. Asked 10 years, 1 month ago. Active 5 months ago. Viewed k times. Erin Tucker Erin Tucker 3, 2 2 gold badges 14 14 silver badges 21 21 bronze badges. Add a comment. How do you determine the data type of a variable in PHP?

How to add a new line within echo in PHP? November 13, October 9, admin 0 Leave a Reply Cancel reply Your email address will not be published. July 6, October 12, admin 0 Comments how to check database null value in php , how to check if a variable is not null in php , how to check if a variable is null in php , php is null vs empty , php is null vs null , php not null.

See also : How to check if a variable is empty in PHP. See also : How to check if a variable is undefined in PHP. In the following example it will work the same way as JavaScript's undefined check. So how do you actually check if a variable is defined? You check the defined variables. This, is the right answer! And why did the PHP folks decide to have isset return false if the variable is defined and contains null ErasmoOliveira ErasmoOliveira 1, 2 2 gold badges 19 19 silver badges 39 39 bronze badges.

Sumit Thakur Sumit Thakur 71 1 1 silver badge 4 4 bronze badges. PHP 7. So no cigar. Quasimodo's clone Quasimodo's clone 5, 2 2 gold badges 20 20 silver badges 37 37 bronze badges. The only thing it will determine is if a variable is set to null without throwing an error, not if the variable is defined. After saying 'If you just use null! Just edited. Arash Younesi Arash Younesi 1, 1 1 gold badge 9 9 silver badges 20 20 bronze badges.

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