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 numericChangelog
Version | Description |
|---|---|
7.0.0 | Strings 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 →
© 1997–2017 The PHP Documentation GroupLicensed under the Creative Commons Attribution License v3.0 or later.
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