https://www.php.net › manual › en › language.types.null

Setting a variable to NULL is telling it to forget its value without providing a replacement value to remember instead. The variable remains so that you can give it a proper value to remember later; this is especially important when the variable is an array element or object property.

https://www.php.net › manual › fr › function.is-null

Le type null. isset () - Détermine si une variable est déclarée et est différente de null. is_bool () - Détermine si une variable est un booléen. is_numeric () - Détermine si une variable est un nombre ou une chaîne numérique. is_float () - Détermine si une variable est de type nombre décimal.

https://www.w3schools.com › php › func_var_is_null.asp

The is_null() function checks whether a variable is NULL or not. This function returns true (1) if the variable is NULL, otherwise it returns false/nothing.

https://www.php.net › manual › fr › language.types.null.php

Le type null est le type unité de PHP, c'est-à-dire qu'il n'a qu'une seule valeur: null. Les variables non définies et les variables unset () auront la valeur null. Syntaxe. Il y a une seule valeur de type null, et c'est la constante insensible à la casse null. <?php. $var = NULL; ?> Transtyper vers null. Avertissement.

https://stackoverflow.com › questions › 9671659

is_null is the same as === null. Both return true when a variable is null (or unset). Note that I'm using === and not ==. === compares type as well as value.

https://www.phptutorial.net › php-tutorial › php-null

To check if a variable is null or not, you use the is_null() function. The is_null() function returns true if a variable is null; otherwise, it returns false. For example: <?php . $email = null; var_dump(is_null($email)); // bool(true) . $home = 'phptutorial.net'; var_dump(is_null($home)); // bool(false) Code language: HTML, XML (xml)

https://www.slingacademy.com › article › understanding-null-in-php

In PHP, NULL is a special data type representing a variable with no value; understanding its implications is key to writing robust applications. This tutorial illustrates its use through gradually complex examples. The Basics of NULL. When a variable is created without a value, it is automatically assigned NULL.

https://www.w3schools.com › php › php_datatypes.asp

Null is a special data type which can have only one value: NULL. A variable of data type NULL is a variable that has no value assigned to it. Tip: If a variable is created without a value, it is automatically assigned a value of NULL.

https://www.phptutorial.net › php-tutorial › php-is_null

In this tutorial, you'll learn how to use the PHP is_null() construct to check if a variable is null.

https://www.gyata.ai › php › php-null

PHP provides two built-in functions to handle NULL values - is_null() and unset(). The is_null() function. This function checks whether a variable is NULL or not.