php教程

floatval

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

floatval获取变量的浮点值

描述

floatval ( mixed $var ) : float

返回变量 varfloat 数值。

var 可以是任何标量类型。你不能将 floatval() 用于数组或对象。

<?php
$var 
'122.34343The';
$float_value_of_var floatval ($var);
print 
$float_value_of_var// 打印出 122.34343
?>

参见 intval()strval()settype()类型戏法

User Contributed Notes

iliyazelenkog at gmail dot com 02-Nov-2018 10:51
(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').
radler63 at hotmail dot com 16-Feb-2018 12:27
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
T-Soloveychik at ya.ru 03-Mar-2017 02:23
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"
pierpaolocira 15-Nov-2016 11:41
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.
movila dot e dot v at gmail dot com 05-Jul-2016 08:05
<?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
*/
?>
Alexey M 23-Mar-2016 02:28
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($var);
?>
double(13232.95)
zfcb13 at gmail dot com 24-Oct-2015 10:18
More elegant function with selection of decimal point (deafault ,):
<?php
function floatvaldec($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$') ;
?>
brewal dot renault at gmail dot com 26-Feb-2014 09:25
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
PapaPinguoin 31-Oct-2011 07:26
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

?>
secretr at NOSPAM dot e107 dot org 03-Jan-2011 08:37
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"
?>
chris at georgakopoulos dot com 29-Jul-2009 08:12
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);
}
?>
ted devito 09-Mar-2009 09:10
i noticed all (well, unless i missed something) the functions working with decimals destroy trailing decimal places. this function restores them in case you want to be able to display a consistent precision for users.

<?php
function decimal($val, $precision = 0) {
    if ((float)
$val) :
       
$val = round((float) $val, (int) $precision);
        list(
$a, $b) = explode('.', $val);
        if (
strlen($b) < $precision) $b = str_pad($b, $precision, '0', STR_PAD_RIGHT);
        return
$precision ? "$a.$b" : $a;
    else :
// do whatever you want with values that do not have a float
       
return $val;
    endif;
}
?>
info at marc-gutt dot de 26-Aug-2008 03:55
<?php
function floatvalue($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.
Michiel 30-Jul-2008 05:21
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>";
}
?>
steve at opilo dot net 20-Jul-2008 06:07
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)); ?>
leprau at leprau dot de 19-Jul-2007 09:26
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;
}
?>
aa at geb-team dot de 04-Sep-2006 08:03
@pillepop2003 at yahoo dot de

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

use: "/^[0-9-]*[\.]{1}[0-9-]+$/"
instead of: "/^[0-9]*[\.]{1}[0-9-]+$/"
19-Apr-2005 05:30
you can also use typecasting instead of functions:

(float) $value;
pillepop2003 at yahoo dot de 14-Dec-2004 02:38
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
anonymous at start dot be 15-Jun-2004 07:00
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
?>
vickers at hotpop dot com 26-Jan-2004 03:45
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
Zipi 25-Apr-2003 02:51
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)
jason at shadonet dot com 07-Mar-2003 07:07
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.

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