PHP validation only number and number with comma

Question

I'm trying to make validation number with format x or x.xx (4 or 4.21). The format I managed to use regex for the x (single digit) is \ b \ d \ b. For x.xx format (two decimal places) I haven't found the regex pattern yet

$tes = 1;
if(!preg_match('\b\d\b', $tes)){
    echo 'right format';
 }else{
    echo 'not right';
 }

`'~^\d(?:\.\d{1,2})?$~'`, see https://regex101.com/r/GYhamN/1 — Wiktor Stribiżew, Aug 06 '20 at 15:11
why are you using regex to validate a number in the first place? — I wrestled a bear once., Aug 06 '20 at 15:15

score 0 · Answer 1 · answered Aug 06 '20 at 15:42

For x.xx format (two decimal places)

If I understand correctly, you want to take exactly one number before point and two numbers after point. So, I suggest the following regex.

^\d(?:\.\d{2})?$

Details:

^\d: always start with number
(?:\.\d{2}): this is optional. After the first number, we have exactly .xx
?$: we take as many cases as possible

Demo

PHP validation only number and number with comma

1 Answers1