is_null

(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)

is_null — Finds whether a variable is null

Description

is_null(mixed $value): bool

Finds whether the given variable is null.

Parameters

value

The variable being evaluated.

Return Values

Returns true if value 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 declared and is different than 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