PHP Null Variables


 

PHP Null Variables

PHP Null variable is a type that only stores the null value. The Null value indicates that the used variable has no value. The variable only considered null when :

PHP Null variable is a type that only stores the null value. The Null value indicates that the used variable has no value. The variable only considered null when :

PHP Null Variables

PHP Null variable is a type that only stores the null value. The Null value indicates that the used variable has no value. The variable only considered null when :

1. The variable assigned as a null.

2. The value has not set or used unset() function.

It is introduced in PHP 4 and further versions and it is also not case-sensitive.

Let's see the example to understand the Null type :

<?php

    $null = NULL;

?>

If you run this code on your server, it will not show anything on the screen because the variable assigned as a null. Even you can leave the value blank.

Let's see few more example to understand the NULL type in a better way :

<?php

error_reporting(E_ALL);

$text = NULL;

 

if($text == null)

{

    echo "The variable has no value!"."<br/>";

}

if($text === null)

{

    echo "Yes, the variable is equal to null!"."<br/>";

}

if(isset($null))

{

    echo "The variable has been set!";

}

    if(empty($null))

{

    echo "The variable is empty!";

0

}

?>

The output of the above example is : The variable has no value!
                                                        Yes, the variable is equal to null!
                                                        The variable is empty!

1

In the above example we only compare the variable value with the null and it gives different-different result to us.

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