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PHP regex - valid float number
what will be regular expression in php as well as for javascript for float numbers?
I waht to match values like 3, 3.3 or 0.3 and 0
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5 Answers
There is no token for float numbers. If you want to match a float you have to use digit + point + digit, something like this:
\d+(\.\d+)?
PHP:
is_numeric($nb);
JS:
!isNaN(+nb);
Comments
If you want to check if a given string is an int/float:
/^\d+(\.\d+){0,1}$/
If you want to match all numbers that in a given string:
/\b\d+(\.\d+){0,1}\b/g
That should give you what you need
answered Nov 2, 2012 at 9:42
Elias Van Ootegem
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Comments
It depends on what you want :
Only check? do as Florian Margaine said : is_numeric($nb) in PHP for float numbers and ctype_digits($nb) for integers. in JS !isNaN(+nb); for float and typeof($nb) == "Integer" for integers.
If you want to convert your numbers (and check in the same time) :
//for floats
$floatNb = (float) $nb;
if($floatNb != 0 || $nb === "0")//now you are sure that $nb was a float and $floatNb is the float representation
If you got international numbers, use the number formatter from intl extension :
<?php
$fmt = numfmt_create( 'de_DE', NumberFormatter::DECIMAL );
$num = "1.234.567,891";
echo numfmt_parse($fmt, $num)."\n";
Regex are NEVER good for type checking
Comments
Float's can also be written as .3, this would be equal to 0.3 in that case to cover all you'd need:
/((?:\d)?(?:.\d+)?)/
This will group the result as one whole string, without splitting it into subresults.
So this would match 33, 3.3 & .33
