https://stackoverflow.com › questions › 418066

I prefer using not empty as the best method to check for the existence of a variable that a) exists, and b) is not null. if (!empty($variable)) do_something();

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

Learn how to use the isset() function to check whether a variable is set and not NULL in PHP. See examples, syntax, parameters, return value and technical details.

https://www.php.net › manual › en › function.isset

isset () is a language construct that determines if a variable is declared and is different than null. It returns true if the variable exists and has any value other than null, and false otherwise.

https://vitalyn.com › blog › developpement-web › php › verifier-si-une-variable-existe-et-nest...

Vérifier si une variable existe et n’est pas vide en PHP. Ces fonctions sont utiles lorsque vous souhaitez effectuer une validation de données que ce soit en PHP ou WordPress. Isset () isset () détermine si une variable existe. La fonction vérifie en fait si la variable est déclarée et si elle est tout sauf nulle.

https://www.learnphp.org › php-isset-function-with-example

The isset() function in PHP is extremely useful when you want to check if a variable has been defined or not. This function helps avoid errors caused by accessing uninitialized or undefined variables. It returns true if the variable exists and has a value, and false if the variable is not set or is set to null.

https://daztech.com › check-if-variable-exists-php

We can check for the existence of a variable with the php isset () function. If the variable exists, isset () return true. Otherwise, isset () returns false. Below are some examples of using isset () in php to check if a variable exists. $variable1 = "I'm a variable"; if (isset($variable1)) { echo "variable1 exists!"; } else {

https://loadforge.com › guides › understanding-php-conditional-statements-a-guide-to-isset

Using isset() within nested conditional statements allows you to verify the existence of multiple variables or array indices in a structured and clear manner. Example: Nested Checking of Array Elements. Consider a scenario where you need to check the existence of an item deep within a multidimensional array:

https://stackoverflow.com › questions › 11464714

Use isset to check if a variable has either not been set or has been set to null. Use empty to check if a variable == false. null is cast to false and as with isset, no notice is thrown if the variable has not been set.

https://www.php.net › manual › en › function.is-object

Finds whether the given variable is an object. Parameters ¶. value. The variable being evaluated. Return Values ¶. Returns true if value is an object, false otherwise. Changelog ¶. Examples ¶. Example #1 is_object () example. <?php. // Declare a simple function to return an . // array from our object. function get_students($obj) {