PHP replace characters "," in a string number to "."

Question

How to convert a string like "3,2563" to "3.2563",

$number = "3,2563" ;
setlocale(LC_MONETARY,"en_US");
echo money_format("%.4n", $number);

or

$number = number_format($number,4,".","");

Both examples output just 3.0000

Answer 1

The string "3,2563" is not a number, thus - it cannot be used as such. It can easily be converted to a float number, using PHP function str_replace and type casting.

$number = "3,2563";
$number = (float)str_replace(",", ".", $number); // returns (float) 3.2563
// Do whatever you want to do. Now $number is a float.

Using str_replace, the , is replaced with a .

Note that the decimals separator can vary, depending on your PHP configuration.

Answer 2

"3,2563" is a string, you're trying to display a string as a number, that's not possible.

You can replace , with . before changing its type:

$number = "3,2563";
$number = str_replace(',', '.', $number); // get "3.2563"
$number = (float) $number; // get a floating number
setlocale(LC_MONETARY,"en_US");
echo money_format("%.4n", $number); // shows "3.2563"
echo money_format("%.2n", $number); // shows "3.26"

Answer 3

You're using a string ill-formatted for the desired use-case and existing logic you have in your code - i.e. '3,2563'. Let me be more clear. In some countries, a comma is used instead of a decimal to demarcate a whole unit of some currency and fractional units of some currency. In other cases, the comma and decimals indicate a thousand whole unit of some currency. It depends on what you're aiming for which isn't clear based on the example you gave... plus, I'm not aware of every monetary syntax convention.

In any event, the general procedure you want to employ is to remove all the commas or to normalize the number (for example use 32563 instead of 3,2563 if you're going for whole units), do your operations, and then reapply the convention (I assume that they're monetary conventions) that you want at the end. If you just want to replace the comma with a decimal - you can still use str_replace() to accomplish that as well. Build a function or class to do that so you can reuse that code for use with other similar problems.

My recommendation, though it wasn't explicit, is to simply use some str_replace() logic to generate a normalized/indexed number.