floatval

(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)

floatval获取变量的浮点值

说明

floatval(mixed $value): float

获取变量 valuefloat 值。

参数

value

可以是任何标量类型。floatval() 不能用于对象,这样做会发出 E_WARNING 级别的错误并返回 1。

返回值

指定变量的浮点值。空数组返回 0,非空数组返回 1。

字符串很可能返回 0,尽管这取决于字符串最左边的字符。适用浮点数强制转换的通用规则。

更新日志

版本 说明
8.0.0 对象转换时的错误级别已从 E_NOTICE 更改为 E_WARNING

示例

示例 #1 floatval() 示例

<?php
$var
= '122.34343The';
$float_value_of_var = floatval($var);
echo
$float_value_of_var; // 122.34343
?>

示例 #2 floatval() 最左边的字符为非数字的示例

<?php
$var
= 'The122.34343';
$float_value_of_var = floatval($var);
echo
$float_value_of_var; // 0
?>

参见

添加备注

用户贡献的备注 22 notes

up
122
brewal dot renault at gmail dot com
10 years ago
This function takes the last comma or dot (if any) to make a clean float, ignoring thousand separator, currency or any other letter :

function tofloat($num) {
$dotPos = strrpos($num, '.');
$commaPos = strrpos($num, ',');
$sep = (($dotPos > $commaPos) && $dotPos) ? $dotPos :
((($commaPos > $dotPos) && $commaPos) ? $commaPos : false);

if (!$sep) {
return floatval(preg_replace("/[^0-9]/", "", $num));
}

return floatval(
preg_replace("/[^0-9]/", "", substr($num, 0, $sep)) . '.' .
preg_replace("/[^0-9]/", "", substr($num, $sep+1, strlen($num)))
);
}

$num = '1.999,369€';
var_dump(tofloat($num)); // float(1999.369)
$otherNum = '126,564,789.33 m²';
var_dump(tofloat($otherNum)); // float(126564789.33)

Demo : http://codepad.org/NW4e9hQH
up
57
Anonymous
19 years ago
you can also use typecasting instead of functions:

(float) $value;
up
22
Alexey M
8 years ago
There is much easier way to deal with formatted numbers:

<?php
$str
= '13,232.95';
$var = (double)filter_var($str, FILTER_SANITIZE_NUMBER_FLOAT, FILTER_FLAG_ALLOW_FRACTION);
var_dump($var);
?>
double(13232.95)
up
27
PapaPinguoin
13 years ago
To view the very large and very small numbers (eg from a database DECIMAL), without displaying scientific notation, or leading zeros.

FR : Pour afficher les très grand et très petits nombres (ex. depuis une base de données DECIMAL), sans afficher la notation scientifique, ni les zéros non significatifs.

<?php
function floattostr( $val )
{
preg_match( "#^([\+\-]|)([0-9]*)(\.([0-9]*?)|)(0*)$#", trim($val), $o );
return
$o[1].sprintf('%d',$o[2]).($o[3]!='.'?$o[3]:'');
}
?>

<?php
echo floattostr("0000000000000001");
echo
floattostr("1.00000000000000");
echo
floattostr("0.00000000001000");
echo
floattostr("0000.00010000000");
echo
floattostr("000000010000000000.00000000000010000000000");
echo
floattostr("-0000000000000.1");
echo
floattostr("-00000001.100000");

// result
// 1
// 1
// 0.00000000001
// 0.0001
// 10000000000.0000000000001
// -0.1
// -1.1

?>
up
19
anonymous at start dot be
20 years ago
Easier-to-grasp-function for the ',' problem.

<?php
function Getfloat($str) {
if(
strstr($str, ",")) {
$str = str_replace(".", "", $str); // replace dots (thousand seps) with blancs
$str = str_replace(",", ".", $str); // replace ',' with '.'
}

if(
preg_match("#([0-9\.]+)#", $str, $match)) { // search for number that may contain '.'
return floatval($match[0]);
} else {
return
floatval($str); // take some last chances with floatval
}
}

echo
Getfloat("$ 19.332,35-"); // will print: 19332.35
?>
up
8
chris at georgakopoulos dot com
15 years ago
locale aware floatval:

<?php
function ParseFloat($floatString){
$LocaleInfo = localeconv();
$floatString = str_replace($LocaleInfo["mon_thousands_sep"] , "", $floatString);
$floatString = str_replace($LocaleInfo["mon_decimal_point"] , ".", $floatString);
return
floatval($floatString);
}
?>
up
2
secretr at NOSPAM dot e107 dot org
13 years ago
setlocale() and floatval() duo could break your DB queries in a very simple way:

<?php
setlocale
(LC_ALL, 'bg_BG', 'bgr_BGR');
echo
floatval(0.15); // output 0,15
?>

You would need simple workaround like:

<?php
function number2db($value)
{
$larr = localeconv();
$search = array(
$larr['decimal_point'],
$larr['mon_decimal_point'],
$larr['thousands_sep'],
$larr['mon_thousands_sep'],
$larr['currency_symbol'],
$larr['int_curr_symbol']
);
$replace = array('.', '.', '', '', '', '');

return
str_replace($search, $replace, $value);
}

setlocale(LC_ALL, 'bg_BG', 'bgr_BGR');
$testVal = floatval(0.15); // result 0,15
var_dump($testVal, number2db($testVal));

// Result:
// float(0,15)
// string(4) "0.15"
?>
up
2
aa at geb-team dot de
18 years ago
@pillepop2003 at yahoo dot de

<?php
float
('-100.00', array('single_dot_as_decimal' => true)); // whoops, returns -10000
?>

use: "/^[0-9-]*[\.]{1}[0-9-]+$/"
instead of: "/^[0-9]*[\.]{1}[0-9-]+$/"
up
3
steve at opilo dot net
16 years ago
Most of the functions listed here that deal with $ and , are unnecessarily complicated. You can use ereg_replace() to strip out ALL of the characters that will cause floatval to fail in one simple line of code:

<?php $output = floatval(ereg_replace("[^-0-9\.]","",$input)); ?>
up
1
pillepop2003 at yahoo dot de
19 years ago
Use this snippet to extract any float out of a string. You can choose how a single dot is treated with the (bool) 'single_dot_as_decimal' directive.
This function should be able to cover almost all floats that appear in an european environment.

<?php

function float($str, $set=FALSE)
{
if(
preg_match("/([0-9\.,-]+)/", $str, $match))
{
// Found number in $str, so set $str that number
$str = $match[0];

if(
strstr($str, ','))
{
// A comma exists, that makes it easy, cos we assume it separates the decimal part.
$str = str_replace('.', '', $str); // Erase thousand seps
$str = str_replace(',', '.', $str); // Convert , to . for floatval command

return floatval($str);
}
else
{
// No comma exists, so we have to decide, how a single dot shall be treated
if(preg_match("/^[0-9]*[\.]{1}[0-9-]+$/", $str) == TRUE && $set['single_dot_as_decimal'] == TRUE)
{
// Treat single dot as decimal separator
return floatval($str);

}
else
{
// Else, treat all dots as thousand seps
$str = str_replace('.', '', $str); // Erase thousand seps
return floatval($str);
}
}
}

else
{
// No number found, return zero
return 0;
}
}

// Examples

echo float('foo 123,00 bar'); // returns 123.00
echo float('foo 123.00 bar' array('single_dot_as_decimal'=> TRUE)); //returns 123.000
echo float('foo 123.00 bar' array('single_dot_as_decimal'=> FALSE)); //returns 123000
echo float('foo 222.123.00 bar' array('single_dot_as_decimal'=> TRUE)); //returns 222123000
echo float('foo 222.123.00 bar' array('single_dot_as_decimal'=> FALSE)); //returns 222123000

// The decimal part can also consist of '-'
echo float('foo 123,-- bar'); // returns 123.00

?>

Big Up.
Philipp
up
1
Michiel
16 years ago
The last getFloat() function is not completely correct.

1.000.000 and 1,000,000 and its negative variants are not correctly parsed. For the sake of comparing and to make myself clear I use the name parseFloat in stead of getFloat for the new function:

<?php
function parseFloat($ptString) {
if (
strlen($ptString) == 0) {
return
false;
}

$pString = str_replace(" ", "", $ptString);

if (
substr_count($pString, ",") > 1)
$pString = str_replace(",", "", $pString);

if (
substr_count($pString, ".") > 1)
$pString = str_replace(".", "", $pString);

$pregResult = array();

$commaset = strpos($pString,',');
if (
$commaset === false) {$commaset = -1;}

$pointset = strpos($pString,'.');
if (
$pointset === false) {$pointset = -1;}

$pregResultA = array();
$pregResultB = array();

if (
$pointset < $commaset) {
preg_match('#(([-]?[0-9]+(\.[0-9])?)+(,[0-9]+)?)#', $pString, $pregResultA);
}
preg_match('#(([-]?[0-9]+(,[0-9])?)+(\.[0-9]+)?)#', $pString, $pregResultB);
if ((isset(
$pregResultA[0]) && (!isset($pregResultB[0])
||
strstr($preResultA[0],$pregResultB[0]) == 0
|| !$pointset))) {
$numberString = $pregResultA[0];
$numberString = str_replace('.','',$numberString);
$numberString = str_replace(',','.',$numberString);
}
elseif (isset(
$pregResultB[0]) && (!isset($pregResultA[0])
||
strstr($pregResultB[0],$preResultA[0]) == 0
|| !$commaset)) {
$numberString = $pregResultB[0];
$numberString = str_replace(',','',$numberString);
}
else {
return
false;
}
$result = (float)$numberString;
return
$result;
}
?>

Comparing of float parsing functions with the following function:

<?php
function testFloatParsing() {
$floatvals = array(
"22 000,76",
"22.000,76",
"22,000.76",
"22 000",
"22,000",
"22.000",
"22000.76",
"22000,76",
"1.022.000,76",
"1,022,000.76",
"1,000,000",
"1.000.000",
"1022000.76",
"1022000,76",
"1022000",
"0.76",
"0,76",
"0.00",
"0,00",
"1.00",
"1,00",
"-22 000,76",
"-22.000,76",
"-22,000.76",
"-22 000",
"-22,000",
"-22.000",
"-22000.76",
"-22000,76",
"-1.022.000,76",
"-1,022,000.76",
"-1,000,000",
"-1.000.000",
"-1022000.76",
"-1022000,76",
"-1022000",
"-0.76",
"-0,76",
"-0.00",
"-0,00",
"-1.00",
"-1,00"
);

echo
"<table>
<tr>
<th>String</th>
<th>floatval()</th>
<th>getFloat()</th>
<th>parseFloat()</th>
</tr>"
;

foreach (
$floatvals as $fval) {
echo
"<tr>";
echo
"<td>" . (string) $fval . "</td>";

echo
"<td>" . (float) floatval($fval) . "</td>";
echo
"<td>" . (float) getFloat($fval) . "</td>";
echo
"<td>" . (float) parseFloat($fval) . "</td>";
echo
"</tr>";
}
echo
"</table>";
}
?>
up
0
T-Soloveychik at ya.ru
7 years ago
Float value less than 0.0001 (0.0000999999999999995) will be converted by floatval to scientific notation (exponential notation):
<?php

var_dump
(floatval(0.0000999999999999995)); # >> float(0,0001)

var_dump(floatval("0.000099")); # >> float(9.9E-5)

var_dump((string)floatval(0.000099)); # >> string(6) "9.9E-5"
up
0
pierpaolocira
7 years ago
Be aware the last tofloat($num).

In theory it is very useful to have a function "separator-agnostic" (I think "locale based" solutions are useless if you have to parse a user file that can have a locale different to the server).

But this can lead to misinterpretations; in short: "123,456" is "123.456" (so comma used as decimal separator) or "123456" (comma used as thousand separator).

In any case, if you really want to use it, please don't forget that this function doesn't manage negative numbers.
up
-1
zfcb13 at gmail dot com
9 years ago
More elegant function with selection of decimal point (deafault ,):
<?php
function floatvaldec($v, $dec=',') { return floatval(ereg_replace("," , "." , ereg_replace("[^-0-9$dec]","",$v))); }

// examples:
echo '<br>'.floatvaldec('somthing123.456.789,12Euro') ;
echo
'<br>'.floatvaldec('x123,456 789.12 Euro', '.') ;
echo
'<br>'.floatvaldec('123.456 789,12$') ;
?>
up
-1
Zipi
21 years ago
This function converts a string to a float no matter is the decimal separator dot (.) or comma (,). It also converts integers correctly. It takes the digits from the beginning of the string and ignores all other characters.

<?php
function floatval($strValue) {
$floatValue = ereg_replace("(^[0-9]*)(\\.|,)([0-9]*)(.*)", "\\1.\\3", $strValue);
if (!
is_numeric($floatValue)) $floatValue = ereg_replace("(^[0-9]*)(.*)", "\\1", $strValue);
if (!
is_numeric($floatValue)) $floatValue = 0;
return
$floatValue;
}
?>

-Zipi (Finland)
up
-1
jason at shadonet dot com
21 years ago
Instead of using floatval which only appeared in PHP 4.2 you could juse use $variable = (float)$variable

This function doesn't seem to add any functionality that wasn't already there.
up
-1
iliyazelenkog at gmail dot com
6 years ago
(float) would be more performant here (up to 6x times faster).

intval, floatval, doubleval, strva for PHP4 functions (intval, floatval, doubleval, strval), in PHP5 use type casting construction (i.e. '(type) parameter').
up
-2
leprau at leprau dot de
17 years ago
For those of you, who are looking for a function that rips the first,
but longest possible float (or at least integer) from a string,
like 123.45 from the string "Price: 123,45$"

If no useable value is found, the function returns false.

Checks for both comma and dot as decimal-separator,
but does not check for 3 digits between thousands,
so 1,234.5 is as valid as 1,23,4.5 (both will return 1234.5)

12,.3 will return 12
1,000,000 will return 1000.0 !

(if thousands separator is defined,
decimals should be defined too ...
in fact I was too lazy to check for that too)

Here you go, and feel free to optimize the function ;)
<?php
function getFloat($pString) {
if (
strlen($pString) == 0) {
return
false;
}
$pregResult = array();

$commaset = strpos($pString,',');
if (
$commaset === false) {$commaset = -1;}

$pointset = strpos($pString,'.');
if (
$pointset === false) {$pointset = -1;}

$pregResultA = array();
$pregResultB = array();

if (
$pointset < $commaset) {
preg_match('#(([-]?[0-9]+(\.[0-9])?)+(,[0-9]+)?)#', $pString, $pregResultA);
}
preg_match('#(([-]?[0-9]+(,[0-9])?)+(\.[0-9]+)?)#', $pString, $pregResultB);
if ((isset(
$pregResultA[0]) && (!isset($pregResultB[0])
||
strstr($preResultA[0],$pregResultB[0]) == 0
|| !$pointset))) {
$numberString = $pregResultA[0];
$numberString = str_replace('.','',$numberString);
$numberString = str_replace(',','.',$numberString);
}
elseif (isset(
$pregResultB[0]) && (!isset($pregResultA[0])
||
strstr($pregResultB[0],$preResultA[0]) == 0
|| !$commaset)) {
$numberString = $pregResultB[0];
$numberString = str_replace(',','',$numberString);
}
else {
return
false;
}
$result = (float)$numberString;
return
$result;
}
?>
up
-1
movila dot e dot v at gmail dot com
8 years ago
<?php
$price
= '1.299,00 EUR';
//$price = 'EUR 1.299,00';
//$price = '$1,745.09';
//$price = '$14';
//$price = '$.14';


function floatValue($str){
if(
preg_match("/([0-9\.,-]+)/", $str, $match)){
$value = $match[0];
if(
preg_match("/(\.\d{1,2})$/", $value, $dot_delim) ){
$value = (float)str_replace(',', '', $value);
}
else if(
preg_match("/(,\d{1,2})$/", $value, $comma_delim) ){
$value = str_replace('.', '', $value);
$value = (float)str_replace(',', '.', $value);
}
else
$value = (int)$value;
}
else {
$value = 0;
}
return
$value;
}

echo
floatValue($price);
/*
1.299,00
1.299,00
1,745.09
14
0.14
*/
?>
up
-2
radler63 at hotmail dot com
6 years ago
I get the following disturbing results:
var_dump string(10) "0.01333"
echo the string=0.01333
echo (float)string=0
echo floatval(string)=0

The string is an outcome of array_map('str_getcsv', file(...
I can't find the characters 8-10

thanks
up
-5
info at marc-gutt dot de
16 years ago
<?php
function floatvalue($value) {
return
floatval(preg_replace('#^([-]*[0-9\.,\' ]+?)((\.|,){1}([0-9-]{1,2}))*$#e', "str_replace(array('.', ',', \"'\", ' '), '', '\\1') . '.\\4'", $value));
}
?>

It is much shorter and able to handle those one, too:
xx,-
xx,--
xx'xxx,xx

After using floatvalue() you can go forward with number_format() as usual.
up
-4
vickers at hotpop dot com
20 years ago
floatval() does not work with "$35,234.43", as it could not handle the '$' and the ','. The following takes care of all values, such that only numeric and the decimal sign are input into floatval(). (It probably shows I'm an old 'c' guy)...this function only lightly tested.

<?php
function strtflt($str) {
$il = strlen($str);
$flt = "";
$cstr = "";

for(
$i=0;$i<$il;$i++) {
$cstr = substr($str, $i, 1);
if(
is_numeric($cstr) || $cstr == ".")
$flt = $flt.$cstr;
}
return
floatval($flt);
}
?>

Richard Vickers
vickers@hotpop.com
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