PHP Currency Regular Expression

Question

I am trying to find a piece of regex to match a currency value.

I would like to match only numbers and 1 decimal point ie

Allowed

• 10
• 100
• 100.00

Not Allowed

• Alpha Characters
• 100,00
• +/- 100

I have search and tried quite a few without any luck.

Hope you can advise

Answer 1

if (preg_match('/^[0-9]+(?:\.[0-9]+)?$/', $subject))
{
    # Successful match
}
else
{
    # Match attempt failed
}

Side note : If you want to restrict how many decimal places you want, you can do something like this :

/^[0-9]+(?:\.[0-9]{1,3})?$/im

So

100.000

will match, whereas

100.0001

wont.

If you need any further help, post a comment.

PS If you can, use the number formatter posted above. Native functions are always better (and faster), otherwise this solution will serve you well.

Answer 2

How about this

if (preg_match('/^\d+(\.\d{2})?$/', $subject))
{
   // correct currency format
} else {
  //invalid currency format
}