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is_numeric

is_numeric

(PHP 4, PHP 5, PHP 7)

is_numeric — Finds whether a variable is a number or a numeric string

Description

bool is_numeric ( mixed $var )

Finds whether the given variable is numeric. Numeric strings consist of optional sign, any number of digits, optional decimal part and optional exponential part. Thus +0123.45e6 is a valid numeric value. Hexadecimal (e.g. 0xf4c3b00c) and binary (e.g. 0b10100111001) notation is not allowed.

Parameters

var

The variable being evaluated.

Return Values

Returns TRUE if var is a number or a numeric string, FALSE otherwise.

Examples

Example #1 is_numeric() examples

<?php $tests = array(     "42",     1337,     0x539,     02471,     0b10100111001,     1337e0,     "not numeric",     array(),     9.1,     null foreach ($tests as $element) {     if (is_numeric($element)) {         echo var_export($element, true) . " is numeric", PHP_EOL;     } else {         echo var_export($element, true) . " is NOT numeric", PHP_EOL;     } } ?>

The above example will output:

'42' is numeric 1337 is numeric 1337 is numeric 1337 is numeric 1337 is numeric 1337 is numeric 'not numeric' is NOT numeric array () is NOT numeric 9.0999999999999996447286321199499070644378662109375 is numeric NULL is NOT numeric

Changelog

VersionDescription
7.0.0Strings in hexadecimal (e.g. 0xf4c3b00c) notation are no longer regarded as numeric strings, i.e. is_numeric() returns FALSE now.

See Also

  • ctype_digit() - Check for numeric character(s)

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

  • is_null() - Finds whether a variable is NULL

  • 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_null

is_object →

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