Strip out commas and characters in a text box

[Len Whistler]

I have a form that the user can enter a number in the text field and a calculation is then preformed with PHP when the form is submitted.

$amount = $_POST['amount'];

<input type="text" name="amount" size="20" value="">

Any way to strip out commas and any characters that may be entered. I would like an entry like $5000, 5000, 5,000 and $5,000 all to be passed on to the PHP script as 5000. The way it is now the php math script treats 5,000 as a 5 and $5000 as a 0.

[Mwnciau]

preg_replace('#[^0-9]#', '', $_POST['text']);

[Ahri]

$amount = preg_replace('#[^\d]#', '', $_POST['amount']);

That'll strip out all non digits with a regular expression :)

[mlseim]

<?php
$amount = $_POST['amount'];

// replace anything that's NOT 0-9 with "null" (nothing)
$result=ereg_replace("[^0-9]","",$amount);

echo $result;

?>

[Len Whistler]

Thanks for the fast replies.

Now another problem as appeared. $34.34 is calculated as 3434, anyway to let the decimals stay? Thanks

[Mwnciau]

preg_replace('#[^0-9.]#', '', $_POST['text']);

This would probably be better:

preg_replace('#.*?([0-9]*(\.[0-9]*)?).*?#', '$1', $_POST['text']);

[bcarl314]

You may also be interested in using is_numeric:

http://us.php.net/is_numeric

[Len Whistler]

Thanks to all the replies. The code I used was the sample posted by Mwnciau.
preg_replace('#.*?([0-9]*(\.[0-9]*)?).*?#', '$1', $_POST['text']);

I tested it with all sorts of numbers such as 50.00, 50, $49.99, $50, 50.01 and they all were calculated as 50, or a penny difference for $49.99 and 50.01. And 5,000 and 5000 were both calculated as 5000. Thanks

I will look into is_numeric later on.