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is_null

is_null

(PHP 4 >= 4.0.4, PHP 5, PHP 7)

is_null — Finds whether a variable is NULL

Description

bool is_null ( mixed $var )

Finds whether the given variable is NULL.

Parameters

var

The variable being evaluated.

Return Values

Returns TRUE if var is null, FALSE otherwise.

Examples

Example #1 is_null() example

<?php error_reporting(E_ALL $foo = NULL; var_dump(is_null($inexistent), is_null($foo) ?>

Notice: Undefined variable: inexistent in ... bool(true) bool(true)

See Also

  • The NULL type

  • isset() - Determine if a variable is set and is not NULL

  • is_bool() - Finds out whether a variable is a boolean

  • is_numeric() - Finds whether a variable is a number or a numeric string

  • is_float() - Finds whether the type of a variable is float

  • is_int() - Find whether the type of a variable is integer

  • is_string() - Find whether the type of a variable is string

  • is_object() - Finds whether a variable is an object

  • is_array() - Finds whether a variable is an array

← is_long

is_numeric →

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https://secure.php.net/manual/en/function.is-null.php